RS Inclinometers. Our RS branded inclinometers are an excellent and inexpensive choice for professional roofers, carpenters and plumbers but can also be used by those interested in DIY who wish to measure angles of slopes. This handy inclinometer has an easy to read dial with a weighted swivelling needle and is a great addition to any tool box. Easy to use Very accurate to within half a degree Use on metal or wood Magnetic base for mounting on steel framing square or pipe. Features and Benefits