Sound pressure level meter, first introduced in early 2003, allow musicians, sound contractors and others to measure SPL in decibels (dB). A decibel is defined as the unit for measuring relative loudness of a sound. We have expanded our line from one check mate SPL meter to four products in the category. We have sold thousands of units to working musicians, DJs, police departments, sound contractors and racetracks. The CM-160 is similar to our model CM-150, except that it has an internal memory storage, which records the SPL and allows it to be transferred to a computer at a later time. The CM-160 comes complete with a carry case, windscreen, USB cable and software for computer.