INSTALLATION NOTES: 1.Insert bolt through the wheel, washer and training wheel arm. 2.Attach and tighten washer and nut, you will require two wrenches to tighten this propeily. 3.Remove rear axle nut from the bicycle wheel axle. 4.Insert axle though locking brace and fix the raised point to the bicycle frame ends . 5.Determine desired height of training wheels when attached the training wheels should have about 0.5-1cm (1/5 to 3/5in) space from the ground. 6.Tighten axle nut with adjustable wrench . 7.Repeat for another suide.Specification: ? Material: Steel + Plastics + Rubber ?Color: Blue ,Black, Red,White, Purple, Rose ?Size: Wheel: 4.54 inch*4.54 inch*0.98 inch /11.5cm *11.5cm*2.5cm ?Fit: 12-20 inch Bicycles