what gasket are you wanting to replace?if its the gasket that seals your sash and frame when you close sash its either a flat gasket called flipper seal,if its like a small tube its called bubble seal,these just pull out of the groove and replace with new,if its the flat 1 replace with bubble anyway it gives a better seal.hope this helps
shaun www.sdwupvcrepair.co.uk, March 2008
