Frame:20"steel,38*42*28mm Fork:steel,28mm Head parts:Steel B.B. Parts:Steel and three pieces crank,cotter-pin Brake:Front an Frame:20"steel,38*42*28mmFork:steel,28mmHead parts:SteelB.B. Parts:Steel and three pieces crank,cotter-pinBrake:Front and rear caliper brakeTire:Air tire,20*2.125Rim:Steel,28H