As it should be obvious from the rather high price, these are very very high end nipple clamps. For the true nipple clamp bondage lover, these are made from mostly solid brass giving them an attractive gold color. The tension on these clamps is adjusted by turning the black cylinder at the base of the clamp to slowly increase or decrease the pressure.This mechanism allows for very precise, controlled tuning of the intensity. For the nipple player lover these are a must, they will slowly increase pressure with the precise turning & let them slowly feel & prolong the orgasm him or her has from nipple play or nipple torture. With the high high the intense orgasm they are going to feel is worth it. Long lasting. Our customers who love nipple play. love the look, feel, & top quality of these clamps,. Hearing the squeals of pleasure & wetness of the orgasm far out weights the price.