I'm rebuilding my Titan Model 6 Surge-o-Matic Disk brake actuator. It took about 30 seconds to swap these new springs in for the old. Why buy a new actuator when its this easy to rebuild your existing one? One trick was to carefully compress the springs in a vice just enough to allow the nuts to go back on. Only took 1/4" of compression to get the nuts back on. Very Happy!!