Answer atac ame mtb stem3d forged stem body and face straps create extremely strong and lightweight stem opposed clamp bolts compatible with carbon steer tubes all stems come with 35mm spacers top cap and star nut features stack height 40mm weight 100g 30mm 105g 40mm 115g 50mm 125g 60mm 132g 70mm 138g 80mm clamp width 51mm clamp width provides stiff 4 bolt interface rise 0 degree rise these are flat stems which provide a dialed in fit option for multiple frame geometri