Silk'n Disposable Lamp Cartridge ensures the fastest treatment speed and the largest treatment size on the market. Each lamp cartridge includes its own Skin Sensor to detect individual skin tones, taking out the guesswork during treatment. If skin tones are darker than allowable settings, the applicator will not flash, thereby providing you a safe home hair removal experience. The lamp cartridge holds 750 pulses which typically covers the entire body (based on treatment of two legs, both arms, underarms and bikini line).