Easily lock rear wheel hubs in place with these adjustable axle keys. Made of ERGAL, 8mm wide, 2.5mm thick, 70mm length, 7.5mm pegs. 34mm most common for CRG, OTK, Tony, IPK, Italkart, Praga, etc. 30mm for Freeline, Bire/Art, Righetti, etc. 2 axle keys included.