Snowboard Boot with BOA Fit System. Firm-flexing and responsive with the micro-adjustability of a BOA Fit System. Season after season, the Ion sets the bar for responsive feel and out-of-the-box fit. The men's Burton Ion BOA Snowboard Boots take it one step further with high-power micro-adjustable tensioning for the upper and lower boot. Combined with a firm flex, they support full-speed-ahead charging for riders who like to rip. Warm, dry feet and unmatched control for dropping lines and sticking landings are all yours. Features Firm, Supportive Flex It's full-speed-ahead with this boot's firm flex. Micro-Adjustable Fit A Dual-Zone BOA Fit System lets you independently micro-adjust the fit and feel of the forefoot and upper boot for the just the right fit and feel. More Lacing Power Features BOA dual high power system for more tensioning power and control of the instep and lower zone than other BOA systems.