These Retaining Rings feature wide "lobes" or "ears" which offer extra retention surface area against the retained part. The 2304T-5304 family of External, Radial Mount Retaining Rings are available in shaft diameter sizes between 0.156 and 1.000 inches, and groove sizes between 0.120 and 0.860 inches. Ring thicknesses are between 0.025 and 0.050 inches. For slightly thicker variations, see the 2304-5304 family of Retaining Rings with similar shaft and groove diameters.