Fits most 7-1/4", 8", 10" and 12" miter/chop/cutoff and hand held circular saws. * Powered by three alkaline batteries (included). Easy to install and use! * Lightweight (2.12 oz) portable features make for easy installation and operation. * Produces a bright(30 feet), easy-to-see line for dead-on accurate cuts. * Ideal for most large-field cutting applications.