The unique 289 high performance motor mounts used on all 65 and early 66 K Code and GT350 Mustangs used a special thick flat washer and fine thread lock nut on the bottom of the mount.
It's always a good idea to replace these, so you don't have to re-use the old lock nut-plus the new plating looks great!
The thick washers feature the correct zinc plating.
The lock nuts have the proper cadmium plating and are the correct 7/16 x 20 fine thread size.
We put these kits together ourselves due to another kit being on the market with the incorrect coarse thread nuts.
The kit includes 2 washers and 2 nuts to do both sides.
Made in the USA.