The spring on my Delta DP300 suddenly broke and I was looking for a replacement. This part works great. There are no numbers on the springs so finding the correct part is difficult, but after measuring the dimensions it seemed to work. I've never done this repair before and ran into a possible problem: the spring is under significant tension when shipped. You should bring the spring into the holder before releasing the tension by unwinding the wire to which it is connected. If you loosen the tension first, you won't be able to fit it into the mount.