15-Pack Hobbypark Plated Landing Gear Stop Set Wheel Collar 9x4.1mm / 0.35"x 0.16" RC Airplane Parts Replacement Outer Diameter : Approx 9mm / 0.35" Inner Diameter:Approx 4.1mm /0.16" Thickness:Approx 5mm / 0.19" Net Weight:Approx 1.7 g/pc Package Include:15 Pieces Plated Wheel Collar & Screws + 1 Piece hex wrench