![FXR Backshift BOA Boot](http://shop.southsidesales.com/cdn/shop/products/61IUW8HidoL._AC_SL1418_{width}x.jpg?v=1651062888)
STIFFNESS RATING
![](https://cdn.shopify.com/s/files/1/0243/3479/4830/files/6.png)
WARMTH RATING MAX
![](https://cdn.shopify.com/s/files/1/0243/3479/4830/files/10.png)
Lace system
• BOA® H4 Coiler reel
Features
• HydrX™ Membrane
• Rated to -75° C with 1200g insulation
• Molded inner heel flex insert for backward flex control and impact support
• Slip-on removable liner with micro fur lining
• Flex inserts for positive fit & feel, and maximum comfort
• Heavy duty 2mm genuine rubber reinforcements
• Front & rear pant cuff attachment system
• Molded ultra low profile toe box
• 20mm thick EVA midsole for maximum impact absorption
• FXR Aggressive tread with concave footprint for added traction, stability, and floatation for increased grip in winter conditions with toe and heel kick
• Achilles and calf cushion support
• Contoured grab handles for single-handed carrying
• BOA® H4 Coiler reel
Features
• HydrX™ Membrane
• Rated to -75° C with 1200g insulation
• Molded inner heel flex insert for backward flex control and impact support
• Slip-on removable liner with micro fur lining
• Flex inserts for positive fit & feel, and maximum comfort
• Heavy duty 2mm genuine rubber reinforcements
• Front & rear pant cuff attachment system
• Molded ultra low profile toe box
• 20mm thick EVA midsole for maximum impact absorption
• FXR Aggressive tread with concave footprint for added traction, stability, and floatation for increased grip in winter conditions with toe and heel kick
• Achilles and calf cushion support
• Contoured grab handles for single-handed carrying
![](https://cdn.shopify.com/s/files/1/0243/3479/4830/files/hydrxpro.png)
![](https://cdn.shopify.com/s/files/1/0243/3479/4830/files/boa.png)