Rubber insulator for A/C condensor.
Comes in sets of 4.
 
These go on the bracket that mounts to the radiator. These rubber sandwich mounts help to minimize vibration between surfaces.
This is a threaded stud with a 1" diameter, 3/4" height, 5/8" thread length. 
Made of black natural rubber.
 
 
 
Made in the USA.