The Martin Axxon 39 SD features Tri Loc axle cap, Tri Loc roto cup, Tri Loc limb pocket, Balanced Bow Technology, Dual Sync Technology, Helix Cams with Helix Grooves and RRAD Weight distribution system. Axle to axle: 39â?쳌, Brace Height: 6.5625â?쳌, Speed: 333 fps, Let Off: 65-85 percent, Draw Length: 25.5â?쳌-28.5â?쳌.