The Wedge is the most advanced approach to simple and secure installations on portable spas. It requires no silicone and allows for inconsistent hole sizes. It also provides a lower profile.
Notice the “wedge” shape of the thick grey gasket, it is a compression seal and eliminates the need for spot facing (smoothing) the back surface. Requires 4″ hole, face plate is 5.16″ wide and this fitting is available in both 2″ and 2.5″ slip . Available at waterwayparts.com
640-6307 v (grey) 2 ” 640-6311 v (black) 2.5″
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