On the bottom side of the isolator, tapered bores and annular grooves surrounding each bore increase flow and prevent reversion from reaching the carburetor.
A ¼-inch aluminum plate is encapsulated and bonded within the special durometer rubber, effectively isolating harmful engine vibrations from migrating to the carburetor.
Two design 4150s: A new design 4150 isolator has a smaller footprint, allowing it to be used in applications where attachment size is a consideration.