Head bolt bushings for your Ford.
Ford: 289-302, 7/16 in. bolt with 1/2 in. bore, head bolt reducer bushing
Are you looking for a head bolt reducer bushing for your Trick Flow heads? If your block uses a smaller diameter bolt than your head does, than this is what you need. It provides the extra space to ensure the proper fit.
Sold as a pack of 20.

Trick Flow Head Bolt Bushings Head Bolt Bushings, 1/ 2 in. to 7/ 16 in., Ford, Small Block, Set of 20