Key Points: Delivery in 3-5 days Can be clipped into a Rafter Supported Glazing Bars Can be pushed onto the edge or front of Polycarbonate Sheeting Available in White and Brown Suits 10mm Twinwall, 16mm Multiwall and 25mm Multiwall Polycarbonate PVC F Sections are most commonly used on lean to roofs installed on top of timber. PVC F Sections should be used when installing polycarbonate glazing on timber structures The PVC F-Section is the best way to finish off the edges of your roof when installing the polycarbonate sheets. They can be used in combination with our snap-down rafter-supported glazing bars or on its own and will provide a water-tight, draught-proof seal to the edges of the roof. If they are used in conjunction with the snap-down glazing bars, it will neatly and easily snap into the base of the glazing bar, which will provide a secure weatherproof seal and finish.