# Clamps and clothes pegs > Nipple clamps and clothes pegs work by restricting blood flow, and the real pain arrives when they come off. Defined here, with the safety facts, not taught. - Canonical URL: https://consensualspanking.co.uk/glossary/clamps/ - Section: A–Z - Updated: November 2026 (2026-11-01) - Audience: consenting adults over 18 only. Everything on this site concerns consenting adults over 18. People search for the word and find nothing else about it here, so this is a straight answer about why, along with the facts that matter. The most important one catches almost everybody out: the pain is in the removal. --- ## In short - Clamps and clothes pegs work by compressing tissue and restricting blood flow to the part they hold. - The significant pain arrives on removal, when blood returns, rather than on application. - Numbness means the circulation is compromised, and it is the signal to take them off. - Anybody with a circulatory or nerve condition, Raynaud's or diabetes should not be doing this at all. Everything here concerns consenting adults over 18. ## What it means A clamp grips a fold of skin and holds it there under spring or screw pressure. In kink use the word almost always means nipple clamps, sold in a range of designs, some with adjustable tension and some without. Clothes pegs get used the same way and belong in the same entry, because the mechanism is identical even where the pressure is not chosen. The mechanism is compression. A clamp squeezes tissue and restricts the blood supply to the part it holds, and everything else on this page follows from that one fact. Clamps used on genitals are outside what this site covers. ## Why the site does not cover it This is a site about spanking, and clamps come out of the wider BDSM tradition. But the reason they stay out is more specific than a question of subject matter, and it is the same reason [figging](https://consensualspanking.co.uk/glossary/figging/) is absent. Everything written here assumes a scene can be halted within a second. That is what a safe word is: an instrument that works because the hand stops and the position ends. Red is only meaningful where stopping is actually available. See [safe words](https://consensualspanking.co.uk/guide/safe-words/). Saying red does not undo a clamp. Removal takes time to do properly, and the worst of the pain is in the removal itself, so the moment somebody most wants it over is the moment that costs the most. That is a different shape of thing from an implement, which stops when the hand stops. So this entry gives the word a definition and carries the safety facts, because people will do it whether or not a reference site approves of it. None of what follows is instruction in how. ## Where people go wrong Expecting the pain to be in the application. It usually is not. Putting one on is manageable for most people. Coming off is the part that makes people swear, because blood floods back into tissue that has been starved of it, and I have never met anybody who was warned about this in advance. If one thing on this page is useful, it is that. Reading numbness as endurance. It means the circulation is compromised, and it is the signal to take everything off. The safe window is short, shorter than almost everybody assumes, and the longer anything stays on the worse the removal becomes. There is no reliable figure in minutes and anybody quoting one is guessing. Prolonged compression risks damage to nerve and tissue that does not announce itself while it is happening. Clothes pegs get treated as the cheap, harmless version. Their spring pressure is uncontrolled and varies from peg to peg, so two out of the same bag are not the same tool, and there is no way to ease one off by degrees. Wooden ones split, and a split peg is a set of sharp edges held against skin. And leaving the timing to the person receiving. Somebody deep in a scene is a poor judge of their own state, which is true of spanking as well but matters more here, because the cost of a bad judgement carries on accumulating while nobody is watching. Whoever puts them on owns the clock. > **Not a matter of judgement.** Anybody with a circulatory condition, a nerve condition, Raynaud's or diabetes should not be doing this at all. Restricting blood flow in somebody whose circulation or sensation is already unreliable is a straight no, and the person concerned will not always volunteer the information unless somebody asks. ## Read next - [Safe words](https://consensualspanking.co.uk/guide/safe-words/) - [Figging](https://consensualspanking.co.uk/glossary/figging/) - [Health conditions and medication](https://consensualspanking.co.uk/guide/health-and-medication/) - [Edge play](https://consensualspanking.co.uk/glossary/edge-play/) ## Common questions ### What are nipple clamps? Nipple clamps are small devices that grip a fold of skin and hold it under spring or screw pressure. They work by compressing tissue and restricting the blood supply to the part they hold. Clothes pegs get used in the same way and behave the same way. This site defines the term and does not cover the practice, which belongs to the wider BDSM tradition rather than to spanking. ### Why do clamps hurt more coming off than going on? Because the significant pain comes from blood returning to tissue that has been compressed and starved of circulation, and that return is much sharper than the pressure ever was. Most people expect the application to be the hard part and are caught out by the opposite. The longer a clamp stays on, the worse removal gets, which is why numbness is the signal to take it off.