CVFC525 Flex Clip Flex Clip for connecting flexible ducting to fan spigot & other equipment. 525mm maximum spigot diameter. £3.98 inc. VAT (where applicable) Pack of Ten (+£27.62): [None]CVFC-525 x 10 Pack Saver Quantity: at £3.98 each Add To Basket 0 in your basket View Basket Checkout Duct worm drive clips have been specifically designed for fixing flexible ducting to solid ducting, extractor fan spigots, duct fittings and air terminal devices. 9mm continuously threaded stainless steel band. The unique one-piece locking mechanism with tilting head provides very fast clamping by hand - only final tightening by screw or hex head driver is necessary to complete a perfectly airtight joint.