A fastener (18) for securing a tooth adapter (16) to a tool of an earth moving apparatus; and, at least one boss (12) securable to the bucket for receiving the tooth adapter (16), each of said bosses (12) defining a longitudinal axis, and a transverse through opening (20), each tooth adapter (16) having a through opening (22) and further comprising: a fastener body (32) shaped to fit through the transverse through opening (20) in the boss (12); a threaded bolt (36) locatable within the fastener body (32); a cam (56, 58) attachable to the bolt (36); and, drive means (42) within the fastener body (32) for rotating the cam (56, 58), whereby the cam (56, 58) engages the interior of the through opening (22) in the tooth adapter (16), drawing it firmly back onto the boss (12), and holding it securely on the boss (12).