The USB is for heating that dildo beside. Product Overview and Target UsersOur sex machine is designed for use by adult men and women ,suits indoor play, you can have a lot of kinds of play, you can change different posture, change different fittings, change different Angle, change different speed,With a variety of angles and speeds, you can try different speed of the same angle or different angles of the same speed. The machine does not need to be charged, and when you want to use it, plug it directly into the home power socket, and the home power supply provides powerful power for the machine. . Machine works with super power of maximum telescopic frequency: 450/minute. The mahcine can be 0 ~ 85degrees dfferent positions adjusted, can adapt to your need. Machine Input: 100 V - 240 V, 30/40 Hz Output: DC 3-24 V, 100-1000 mA Telescopic Speed: 0 - 450/minute