Inside pipe cutter kit installation sequence: extension rod (first) - serrated washer - saw blade - flat washer - screw (last). The screws must be tightened and reinforced. Refer to the fourth photo for example. A PVC pipe internal cutter with 4 saw blades (3 blades with 1.25 inch diameter and 1 blade with 1.75 inch diameter), and two sets of screw fastening parts. Please install the saw blade. There is a layer of protective oil on the saw blade. The saw handle is made of heavy-duty carbon steel for hardness, durability and surface strength. The saw blade is strong, durable and sharp, very suitable for PVC and plastic pipes. It can also be used for soft metal pipes; when cutting soft metal pipes, please use coolant or water during cutting to prevent the saw blade from overheating. The overall length of pipe cutter is 10.5 cm (4.13 inch), and the length of the hexagonal handle is 2.8 cm (1.1 inch). The pipe cutter is compatible with most electric drills and is very easy to install and replace. Small in size and easy to carry, it is suitable not only for external cutting but also for applications where pipes need to be cut from the inside. Three major precautions: 1. Always wear gloves and goggles when using tool accessories and be aware of your surroundings. 2. The maximum speed of the saw blade should not exceed 20,000 rpm. 3. Keep out of reach of children to prevent injury. Material: Carbon steel Color: Silver Package Contents: 1 set x Internal pipe cutter Only the above package content, other items are not included. Note: Light reflection and different displays may cause the color of the item in the image to vary slightly from the real thing. The measurement allowed error is +/- 1-3 cm.