4 BestFlex 13 X 13 Top Plate With 3 High Clamping Collar. The BestFlex Top Mounting Hardware consists of the Top Plate with a 3 high clamping collar and the easy to attach Rain Caps. The Top Plates are available with an OD of 9 X 13 , 13 X 13 and 18 X 18. BestFlex Liner slides up through the collar in the plate and is secured with the tightened hose clamp. The Rain Caps slide over the bead at the top of the collar and secure with the hose clamp.
