Adapter sleeves are always supplied with a locknut and locking device. They can be ordered in metric or imperial dimensions, or to a customised design. A hydraulic process also enables easy installation and removal. With this design, the adapter sleeves and withdrawal sleeves have oil grooves and oil ducts. As adapter sleeves are used as bearing accessories, their product codes are based on the system for coding bearings. The product codes for adapter sleeves with metric dimensions start with H, even if the bore is given in imperial dimensions. Adapter sleeves starting with SNW and SNP are only ever produced in imperial dimensions.