Isolation mounts are used to attach and position systems, accommodate displacement, and isolate components from the surrounding structure (vibration, shock, noise). Mount Type: Two-Piece - Symmetric Head Outside Diameter (mm): 89 Head Outside Diameter (in): 3.5 Head Thickness (mm): 15 Head Thickness (in): 0.59 Pilot Outside Diameter (mm): 66.5 Pilot Outside Diameter (in): 2.62 Inside Diameter (mm): 34.9 Inside Diameter (in): 1.38 Mount Height (mm): 79 Mount Height (in): 3.11 Bonded Sleeve: Yes Standard Bolt Size: 1-1/4"