The forces that are thrown at your stem during BMX racing are incredible! During the gate start you're trying to pull the bike apart as you crank down on the pedals, and pull on the 'bars. Not to mention that case on that huge set of doubles that you hope no one saw! The Box Delta Stem can handle all this, and more! It is the first, modern, 31.8 ’…, oversize stem designed specifically for BMX racing. When used with our new Jet, Triple Taper Alloy, or Box One Chromoly (aka Maximus) handlebars, you get the absolute stiffest cockpit available. This added stiffness significantly improves bike handling while putting more upper body power into your pedal stroke, translating into more forward momentum. This isn't just hype. Every rider we've worked with who has used the Delta/Maximus set-up has noticed a major improvement in stability and control. Delta stem bodies are extruded and CNC-machined from the highest quality 6061-T6 aluminum. The top clamps are cold forged and CNC-machined for increased stiffness and strength. Despite their size and girth, Delta stems weigh less than many standard size 22.2 stems. Clamp 31.8mm Extension 48mm, 53mm, 60mm Material 6061-T6 Aluminum Stack Height 34.5mm Steerer 1 1/8" Weight 290g (48mm), 299g (53mm)