Nipple pumping is a type of nipple stimulation, and is performed by attaching a suction device to the nipple called nipple pump that causes an increase in blood flow, and therefore an increase in sensitivity. Pumping can be achieved by as basic an item as a snake bite kit rubber suction cup, or as elaborate as an electric pump that pulses suction like a breast pump used for expressing milk in lactating women. Nipple pumping can be performed as a therapy for someone suffering from inverted nipple. The effect of using a nipple pump are erected nipples. The nipples while remain in a highly erected state between 3 to 10 minutes after the nipple pump is removed. Most women report that their nipples are far more sensitive during that phase and more open to other types of nipple stimulation. Too much pressure or teasing however can also lead to pain. Frequent usage of nipple pumps (once every day for 10 minutes) will loosen the nipple tissue and thus leading to longer and thicker nipples. e.g. when erected. The cups attached to pumps for nipple pumping only cover her nipples and only apply the low pressure onto her nipplers and areolas. If her entire breast is covered by the suction cup, it is called a low vacuum breast pump. Nipple pumping is also used during socalled nipple torture. If a nipple pump is applied on pregnant tits and generates milk, it is called milking.