10mm compression straight coupling for copper tube Compression fittings are ideal for working in confined spaces where copper pipe would be difficult to solder. The fittings are composed of an outer compression nut and an inner compression olive Thread sealants such as joint compound and PTFE tape are unnecessary on compression fitting threads, as it is not the thread that seals the joint but the compression of the olive. It is critical to avoid over-tightening. If the nut is overtightened the olive will deform improperly causing the joint to fail.
