US Patent 10071474 Cutting guide and method of installing exhaust tube

A cutting guide serves to adjust a length of an exhaust tube introduced in an exhaust pipe so as to adapt to combination of the exhaust pipe communicating from the inside to the outside of a building with an exhaust terminal attached to an end portion of the exhaust pipe on an outdoor side. The cutting guide has a reference site for alignment with an exhaust pipe unit including the exhaust pipe, and has an indication of a cutting position of the exhaust tube for adjusting a length of the exhaust tube protruding from the end portion of the exhaust pipe portion on the outdoor side to a length adapted to a type of the exhaust terminal.