Mortise chains is often used as a synonymous for set, the complete tool made of a chain, guide bar and sprocket for the production of slots of different dimensions in the wood.
The set is mounted on mortising machines, which may be stationary or portable.
The stationary machines are generally of Italian and German manufacture, and have a guide-sprocket centre of 150 mm.
The portable machines are generally of German and Japanese manufacture, and have a centre of 70 mm.
However, many other mortising machines with different centre are also in operation.