Pontoon Post Guide-OnLoading your pontoon boat onto your trailer is much easier with post guide-ons. These guide-ons mount on top of rear cross member and fit in between the pontoons to center your boat on the trailer. Steel arms are made of 1-1/2" galvanized tubing and extend fully into sturdy 2" PVC tubes. Fit up to 3" x 4-1/4" frames. 22" high. Sold in pairs.