Originally the PIR (passive infrared) covert security cameras were developed as a method for monitoring cash registers in retail stores, the PIR camera has evolved into one of the most versatile covert cameras available. At home, in the office, warehouse or manufacturing environment, the PIR camera is available in hardwired models with a down view camera in one area, makes this the perfect choice for a small or a medium sized business. All of the PIR security cameras have a 3.7mm pinhole mini lens. The color cameras have 480 lines of resolution and low 0.4 lux rating.