button hidden camera is great for on-the-go application. it is one of the most popular surveillance item requested for spy or undercover surveillancing. this button hidden camera is undetectable, and is a standard size button. button hidden cameras will allows the user to integrate a micro camera into their clothing. since this is a body-wear hidden surveillance, we include a 700mw transmitter ( built-in rechargeable lithium battery) and 4channel receiver ( built-in rechargeable lithium battery)! button camera features: color 1/4 ccd image sensor( not the cheaper cmos!). rule:pal/ccir ntsc/eia. effective picture element :pal:628x582 ntsc:510x492. horizontal definition :420 line. minimum illumination: 0.5 lux. frequency: 1.2 ghz / 4 channel. transmitter power: 700mw can up to 500 meters. size: 89 x 57 x 21mm. frequency: 1.2 ghz / 4 channel. built-in rechargeable lithium battery can continuum work 3 hours. power supply : dc 12v. size:115 x 62 x 24mm. more surveillance products info pls visit our website at www.szkws.com