Free Shipping 10pcs Coupler Coupling Boat Motor shaft converter adapterfor RC Boat Models 3.17mm 4mm 5mm 2mm 2.3mm 6mm 6.35mm 7mm 8mm 10mm
Material:6063 aluminum alloy
You can find more dimensions from below link,
https://product/Free-Shipping-10pcs-Aluminium-alloy-coupler-for-RC-Boat-shaft-motor-connector-joint-2-2-3/2414051_32749734417.html
Package include:
10x Coupling
40x M4 mini screws
1x Simple wrench