Made from billet alum. these plug tube seals pop in the valve cover, spin the knurled nut down on the back side, drop your plug tube down inside the seal adapter that has an O-ring to prevent seepage and you are ready to fire the motor up.
Plug tube seals are sold in a set of eight, with eight O-rings and eight knurled nuts. Plug tube seal measures .600" from valve cover surface to the top of the seal and is 1.740" in diameter. Register to go down in the valve cover is 1.50" and inside diameter is 1.260" where the spark plug tube slides down into the plug tube seal.
If the buyer likes they can top off the plug tube seal with a set of rubber plug boots #2500-0154 for a super clean plug wire installation. The top of the billet plug seal has a relief machined into it to allow the plug boot to clip on.
*** NOTE TO THE BUYER OVER THE YEARS THE VALVE COVERS THICKNESS AND PLUG TUBE HOLES SIZE DID CHANGE FROM DIFFERENT BATCHES SO SOME GRINDING OR MACHINING COULD BE POSSIBLE TO MAKE THE FIT PERFECT.