Our water pump spacers are great when the water pump must be spaced away from the block for clearance reasons. This is usually done when running a gear drive or belt drive, or for belt alignment, or any type of custom installation. These are 1/4" (.250") thick. Made from 6061 T-6 Aluminum in the good old US of A. Sold in a set of 2 pieces, at a price you won't find anywhere else.