outer diameter approx. 136 mm, inner diameter approx. 70 mm, height approx. 18 mm - front/top side fully rubber bonded with sharp edge, one step - rear/bottom side with two steps, second step approx. 7 mm height - part of piston kit O-PIK-5L40E (models from 2002-up) - does not retrofit older models this item is normally not available as a single part - only if we find surplus stock, we will offer and sell this product - if it is on sale it is only available until quantity in stock is sold - subject unsold - use Seal-E-Zee for installation of the pistons !