“One Revolution” Internal Tube Cutter cuts off tubes in one revolution (in Condensers, Heat Exchangers and Boilers). This “One Revolution” Internal Tube Cutter is designed for hand operation using a Ratchet handle. The Cutter Tool Bit operates on eccentric principle. The Tube Cutter is placed in the tube with the Tool Bit in closed position, Ratchet is applied and turned in clockwise direction. The Tool Bit contracts the tube during the One Revolution and pierces the tube wall and as turning is continued the Tool Bit shears through the tube along its circumference. This Cutter is fitted with an adjustable collar enabling it to reach into tubes up to various distances.