... . 4. It powered by iPhone, just connect it to iPhone for use. 5. No need to use blowpipe, just blow into air hole, this way ... .Information:* please connect this product to Iphone , then unlock Iphone, then press switch of tester for 2-3 seconds, at the same ... display shows countdown 6 seconds, please blow to air hole and exhale into sensor for 3 to 5 seconds , after finishing Countdown ,display ...