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Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Union Astra Step On®
Model Information

Union Astra Step On®

Women's Snowboard Binding

¥60,500
¥60,500
Sold out
Tax included. Shipping calculated at checkout.
Black White Lilac
S M L
Size Chart
Only 2 left Only 3 left Only 0 left Only 2 left Only 3 left Only 0 left Only 2 left Only 3 left Only 0 left

Find My Size | Based on Women’s Step On® Sizingarrow icon union

Select
US
EURO
UK
MONDO
Select
*-5.5
5.5-7.5
8-10
10.5-13
13-15
2-4.5
4.5-6.5
7-9
9.5-12
12-14
34-37
37-40.5
41-43
43.5-46
46-48
21-23.5
23.5-25.5
26-28
28.5-31
31-33
4-6.5
6.5-8.5
9-11
2-4.5
4.5-6.5
7-9
34-37
37-40.5
41-43
21-23.5
23.5-25.5
26-28
11C-3K
3K-5.5K
5.5K+
10K-2
2-4.5
4.5-6.5
28-34
34-37
37-40.5
17.5-21
21-23.5
23.5-25.5
6-8
8.5-10.5
11-13
14-15
5-7
7.5-9.5
10-12
13-14
38-41
41.5-43.5
44-46
47-48
24-26
26.5-28.5
29-31
32-33
5-6
6.5-8.5
9-11
3-4
4.5-6.5
7-9
35-36.5
37-40.5
41-43
22-23
23.5-25.5
26-28
YOUR SIZE IS: Mini XS S M L XL
STEP ON® bindings are ONLY compatible with STEP ON® boots.
Must select color and size.

• Free Shipping • Easy Returns • Official Warranty

Main Information

Union Astra Step On®

Fast in. Fast out. Locked in for total control. The Union Astra Step On® brings the proven convenience of Step On® technology to women’s all-mountain performance. Featuring the Step On® Instant Connection™ System, the Astra delivers lightning-fast entry and exit without sacrificing response, precision, or power.

Union Binding Company is the only licensing partner developing and producing its own products, which feature the Step On® Instant Connection™ System.

Riding Category
Freestyle Rating: Freestyle bindings are designed for riders looking for the ultimate freedom, comfort and that “loose truck” feel. These bindings are generally best suited for riding park or riders looking for a more soft and surfy board feel.

All Mountain Rating: All Mountain bindings are generally mid-flexing and built to handle all terrain and all riding styles.

Performance Rating: Performance bindings are stiffer, provide instant edge-to-edge response, and the most stable board connection possible. Performance bindings are generally best suited for high speed carving or ridding steep technical terrain.

Freeride Rating: Freeride bindings are built for off-piste exploration, deep powder, and challenging backcountry conditions. They combine support, comfort, and responsiveness, allowing riders to tackle variable snow and steep terrain with confidence.
freestyle
Freestyle
Good
Great
freestyle
All Mountain
Good
Great
freestyle
Performance
Good
Great
freeride
Freeride
Good
Great
KEY FEATURES
  • Step On® Instant Connection™ System
  • Adjustable Forward Lean
  • Adjustable Gas Pedal
  • Hi-Flex EVA Bushing
Weight
All listed binding weights area based on a size medium full pair, including disks and hardware. Actual product weight may vary by +/- 1%, and slight differences can occur between colorways.

1.60 KG

Binding Flex
Union Bindings come in a variety of flex ratings. The baseplate, highback, straps, bushing and disk all have different stiffnesses to help give a specific ride feel and function. Softer flexing bindings are generally used for more surfy or freestyle riding, while stiffer bindings are generally used for more hard charging and responsive freeriding.

6/10

FLEXY
RIGID
warranty union
THE UNION WARRANTY Lifetime for baseplate / heelcup,
2 year for everything else.
Rider: Halle McRae
Filmer: Marcos Miranda
Specifications

Key Features

{"baseplate":{"active":true,"title":"S1 Step On® W Duraflex ST Baseplate","description":"Union strength and dependability + the easy-to-use performance of the Step On® Instant Connection™ System. The engineering team at Union has spent countless hours perfecting the S1 Step On® W Duraflex ST Baseplate. Backed by Union's lifetime warranty guarantee.","rating":"60","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_base.jpg?v=1780560180"},"highback":{"active":true,"title":"S1 Step On® W Duraflex ST Highback","description":"The S1 Step On® W Duraflex ST Highback combines legendary Union performance with the easy-to-use Step On® Instant Connection™ System. Equipped with two stages of forward lean, you can easily dial in the highback to suit your preferred riding style.","rating":"60","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_hb.jpg?v=1780560180"},"anklestrap":{"active":false,"title":"Exoframe 5.0","description":"The Exoframe 5.0 ankle strap utilizes tri-axial progressive flex for the perfect boot to binding fit and provides instant power and response when you’re ready to lay down hard charging, high speed carves. Easily adjust your ankle strap to any boot with the quick snap of the pin adjustment, no tools needed.","rating":"70","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN24_ATLAS_BRONZE_ANKLE_STRAP.jpg?v=1708505921"},"toestrap":{"active":true,"title":"Step On Instant Connection™ System","description":"Fast in, fast out. The Step On® Instant Connection™ System is the only automatic binding system that meets Union's standards of performance, durability, comfort, and function. Simply step into the binding heel-first to engage the heel clip, then press down on your toes until you hear the clicks. When it's time to get out, pull the lever on the heel of the binding and twist your foot. It's that easy.","rating":"","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_front_tower.jpg?v=1780560181"},"ratchets":{"active":false,"title":"Magnesium S1 w\/ Steel Base","description":"Magnesium S1 ratchets are Union’s answer to the elements. A fully integrated spring protected from the harsh outside provides you with Union’s best ratchet to date. Longer life span and better spring return guaranteed.","rating":"","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN24_ATLAS_BRONZE_RATCHET.jpg?v=1708505921"},"gaspedal":{"active":true,"title":"Non-Stick HP EVA Footbed","description":"The next evolution of Union's non-stick EVA technology. Non-Stick Hot Press EVA creates a closed-cell, 100% waterproof surface that prevents snow and ice buildup underfoot. Designed to absorb vibration and cushion impacts, it delivers a smoother ride with lasting comfort. Easily adjusts for the perfect fit with your boots.","rating":"","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_disk_cover.jpg?v=1780560182"},"frontbaseplatelogo":{"active":true,"title":"Hi-Flex EVA Bushing","description":"Hi-Flex EVA bushings act as an additional layer of dampening and shock absorption between you and your snowboard and never loose shape over time. Your knees and feet will thank you.","rating":"","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_bushing.jpg?v=1780560180"},"flad":{"active":true,"title":"Step On Instant Connection™ System","description":"Fast in, fast out. The Step On® Instant Connection™ System is the only automatic binding system that meets Union's standards of performance, durability, comfort, and function. Simply step into the binding heel-first to engage the heel clip, then press down on your toes until you hear the clicks. When it's time to get out, pull the lever on the heel of the binding and twist your foot. It's that easy.","rating":"","img":"https:\/\/cdn.shopify.com\/s\/files\/1\/0296\/3764\/0285\/files\/UN26_ASTRA_StepOn_rear_lever.jpg?v=1780560181"}}
Union Astra Step On®
exoframe bindings

S1 Step On® W Duraflex ST Baseplate

Union strength and dependability + the easy-to-use performance of the Step On® Instant Connection™ System. The engineering team at Union has spent countless hours perfecting the S1 Step On® W Duraflex ST Baseplate. Backed by Union's lifetime warranty guarantee.

Baseplate Flex

Flexy
Rigid
exoframe bindings

S1 Step On® W Duraflex ST Highback

The S1 Step On® W Duraflex ST Highback combines legendary Union performance with the easy-to-use Step On® Instant Connection™ System. Equipped with two stages of forward lean, you can easily dial in the highback to suit your preferred riding style.

Highback Flex

Flexy
Rigid
exoframe bindings

Exoframe 5.0

The Exoframe 5.0 ankle strap utilizes tri-axial progressive flex for the perfect boot to binding fit and provides instant power and response when you’re ready to lay down hard charging, high speed carves. Easily adjust your ankle strap to any boot with the quick snap of the pin adjustment, no tools needed.

Anklestrap Flex

Flexy
Rigid
exoframe bindings

Step On Instant Connection™ System

Fast in, fast out. The Step On® Instant Connection™ System is the only automatic binding system that meets Union's standards of performance, durability, comfort, and function. Simply step into the binding heel-first to engage the heel clip, then press down on your toes until you hear the clicks. When it's time to get out, pull the lever on the heel of the binding and twist your foot. It's that easy.

exoframe bindings

Magnesium S1 w/ Steel Base

Magnesium S1 ratchets are Union’s answer to the elements. A fully integrated spring protected from the harsh outside provides you with Union’s best ratchet to date. Longer life span and better spring return guaranteed.

exoframe bindings

Non-Stick HP EVA Footbed

The next evolution of Union's non-stick EVA technology. Non-Stick Hot Press EVA creates a closed-cell, 100% waterproof surface that prevents snow and ice buildup underfoot. Designed to absorb vibration and cushion impacts, it delivers a smoother ride with lasting comfort. Easily adjusts for the perfect fit with your boots.

exoframe bindings

Hi-Flex EVA Bushing

Hi-Flex EVA bushings act as an additional layer of dampening and shock absorption between you and your snowboard and never loose shape over time. Your knees and feet will thank you.

exoframe bindings

Step On Instant Connection™ System

Fast in, fast out. The Step On® Instant Connection™ System is the only automatic binding system that meets Union's standards of performance, durability, comfort, and function. Simply step into the binding heel-first to engage the heel clip, then press down on your toes until you hear the clicks. When it's time to get out, pull the lever on the heel of the binding and twist your foot. It's that easy.

Specifications

Binding Details

Technology
Baseplate
NEW S1 Step On® W Duraflex ST
Union dependability + the easy-to-use performance of the Step On® Instant Connection™ System.
Bushing
NEW Hi-Flex HP EVA
A responsive, waterproof, and vibration canceling layer between the baseplate and your snowboard.
Heelcup
NEW Extruded 3D Aluminum
Designed for optimum heel hold and minimization of drag. Lifetime warranty.
Highback
NEW S1 Step On® W Duraflex ST
Legendary Union performance + easy-to-use Step On® Instant Connection™ System.
FLAD
NEW Integrated 2-Stage
Quickly adjust your forward lean angle to suit the terrain in front of you.
Hardware
NEW Grade 8.8 Steel
The strongest steel available on the market.
Gas Pedal
NEW Non-Stick HP EVA
Vibration-dampening EVA that prevents snow and ice buildup under your boots.
Canting
No
Suggested Board to Binding Flex

Boards and bindings come in a variety of stiffnesses for different types of riding. Every rider has their own preference on how a board and binding should interact. Below is Union's suggestion of board to binding flex.

suggested board bindings suggested board bindings
Soft
Stiff
Disk Type and Compatibility
disk bindings

Step On® 4x2 Disk + Washer

disk bindings

4x2

disk bindings

Step On® Channel Disk

disk bindings

Channel

Rider Video
Images

Gallery

union Union Astra Step On®
union Union Astra Step On®
union Union Astra Step On®
union Union Astra Step On®
union Union Astra Step On®
Step On®

FAQs

What boots are Union Step On® bindings compatible with?
Union Step On® bindings are compatible with any Step On® model boot - Burton, Nitro, DC, etc.
What mounting systems are Union Step On® bindings compatible with?
The Union Atlas Step On® binding is compatible with 4x2 and the Channel.
Does Step On® work in powder?
Yes, Step On® bindings work in all riding conditions. As with any snowboard binding, be sure to brush off any excess snow from the binding and bottom of your snowboard boot before entering.
Who should I contact for Union Step On® customer support?
All Union Step On® warranties and customer service questions will be handled directly by Union customer support.

Additional Union Gear

You May Also Like

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MEN’S/UNISEX - - - SMALL MEDIUM LARGE X-LARGE
US Men - - - 5.5 - 7.5 8 - 10 10.5 - 13 13 - 15
US Women - - - 6.5 - 8.5 9 - 11 - -
US Kids - - - 5.5K+ - - -
UK - - - 4.5 - 6.5 7 - 9 9.5 - 12 12 - 14
EURO - - - 37 - 40.5 41 - 43 43.5 - 46 46 - 48
MONDO - - - 23.5 - 25.5 26 - 28 28.5 - 31 31 - 33
WOMEN’S - - SMALL MEDIUM LARGE - -
US Men - - * - 5.5 5.5 - 7.5 8 - 10 - -
US Women - - 4 - 6.5 6.5 - 8.5 9 - 11 - -
US Kids - - 3K - 5.5K 5.5K+ - - -
UK - - 2 - 4.5 4.5 - 6.5 7 - 9 - -
EURO - - 34 - 37 37 - 40.5 41 - 43 - -
MONDO - - 21 - 23.5 23.5 - 25.5 26 - 28 - -
KIDS ONE MINI SMALL MEDIUM - - -
US Men - - * - 5.5 5.5 - 7.5 - - -
US Women - * - 4 4 - 6.5 6.5 - 8.5 - - -
US Kids 7C - 11C 11C - 3K 3K - 5.5K 5.5K+ - - -
UK 6 - 10 10K - 2 2 - 4.5 4.5 - 6.5 - - -
EURO 24 - 28 28 - 34 34 - 37 37 - 40.5 - - -
MONDO 13.5 - 17.5 17.5 - 21 21 - 23.5 23.5 - 25.5 - - -
CROSSOVER SIZING
MEN'S
 - - - SMALL MEDIUM LARGE X-LARGE
US Men's Boot Size - - - 6 - 8 8.5 - 10.5 11 - 13 14 - 15
UK Boot Size - - - 5 - 7 7.5 - 9.5 10 - 12 13 - 14
CM Boot Size - - - 24 - 26 26.5 - 28.5 29 - 31 32 - 33
EU Boot Size - - - 38 - 41 41.5 - 43.5 44 - 46 47 - 48
Mondo Boot Size - - - 240 - 260 265 - 285 290 - 310 320 - 330
WOMEN'S
 - - - SMALL MEDIUM LARGE -
US Women's Boot Size - - - 5 - 6 6.5 - 8.5 9 - 11 -
UK Boot Size - - - 3 - 4 4.5 - 6.5 7 - 9 -
CM Boot Size - - - 22 - 23 23.5 - 25.5 26 - 28 -
EU Boot Size - - - 35 - 36.5 37 - 40.5 41 - 43 -
Mondo Boot Size - - - 220 - 230 235 - 255 260 - 280 -

STEP ON® bindings are ONLY compatible with STEP ON® boots. Do not use either product with non-STEP ON® boots or non-STEP ON® bindings. Consult the size chart to ensure that you have the correct size binding for your boot size. Pairing incompatible size boots with bindings may lead to malfunction and could compromise your safety. Women’s and Men’s sizing are based on different size standards. Combining men’s and women’s STEP ON® products will result in malfunction and could compromise your safety.

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BINDING FINDER
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01. General Info:

Select
Men
Women
Kids
Find My Size | Based on 's Size Chart arrow icon union
Select
US
EURO
UK
MONDO
Select
*-5.5
5.5-7.5
8-10
10.5-13
13-15
2-4.5
4.5-6.5
7-9
9.5-12
12-14
34-37
37-40.5
41-43
43.5-46
46-48
21-23.5
23.5-25.5
26-28
28.5-31
31-33
4-6.5
6.5-8.5
9-11
2-4.5
4.5-6.5
7-9
34-37
37-40.5
41-43
21-23.5
23.5-25.5
26-28
7C-11C
11C-3K
3K-5.5K
5.5K+
6-10
10K-2
2-4.5
4.5-6.5
24-28
28-34
34-37
37-40.5
13.5-17.5
17.5-21
21-23.5
23.5-25.5
YOUR SIZE IS: One Mini XS S M L XL

02. Riding Ability:

union bindings finderunion bindings finderBEGINNER
union bindings finderunion bindings finderINTERMEDIATE
union bindings finderunion bindings finderADVANCED

03. Riding Style:

FREERIDE
Steep, Deep, Hard Charging
ALL MOUNTAIN / FREESTYLE
Soft and surfy carving
ALL MOUNTAIN
Ride any terrain
STREET / JIBBING
Maximum freestyle flex
ALL MOUNTAIN / FREERIDE
Destroy the resort
CARVING / BOARDERCROSS
Instant edge-to-edge response
FREESTYLE / PARK
Jumps, rails, and pipe
SPLITBOARDING
Climb Up, Ride Down

04. Our Recommendation:

union loader
UNION BINDING CO. 2026/27
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