Jeep CJ model 30 front locking hubs, 27 spline. These are 6 bolt, external locking hubs. They have 27 splines, and will fit both drum and disc brake CJ model 30 front axles from 72 to 80. They will also fit external 6 bolt outer Scout 44 front axles. Remember, in 1981, Jeep changed to 5 bolt outer front hubs.