This invention provides a composition comprising formalin and chloride. The barrier layer has a thickness no greater than 20% of the average thickness of the multi-layer tube, and consists of a homo polymer of chlorotrifluoroethylene having a melting point no greater than 220\xb0 C. The towel dispenser may include a motor for driving dispensing of the toweling from the housing and an associated sensor. The lower end of the sleeve runs in a drilling in the cylinder head as far as the region of the end of the drilling.