A nipple clamp is a device that applies pressure to the nipples with the purpose of pleasure and pain. Clamps usually come in pairs and are linked by a chain.
A nipple pump is a device that forms a vacuum around the nipple to stimulate the nipple and areola. Some nipple pumps vibrate and others have a squeeze pump and release valve that fits over a nipple. Increase pressure with the squeeze pump and decrease pressure with the release valve. Always warm-up the nipple before using a pump. Discontinue use if pain occurs.