Cord locks are often used in conjunction with elastic cord or elastic string. Often made out of plastic, a cord lock is also known as a cord fastener, a plastic stopper, or a cord toggle. The real unique selling point of the cord lock is that it tightens rope or cord without the use of knots. The cord lock is a piece of kit often used by mountaineers to fasten equipment quickly so they don't need to fumble around trying to tie knots.
The cord lock consists of three main parts; a barrel; a toggle or plunger; and a spring. These three parts work together to squeeze and release tension as needed to allow the cord or rope to move through the mechanism. They are available in a number of shapes and sizes and applicable in many scenarios. They can come in a mini size, or as a no spring cord lock or a rim cord lock.
Cord locks and cord fasteners are used to retain one or more rope segments for release as and when required. The most common day manifestation of their usage is in garments such as sweaters, jackets or jogging bottoms that use drawstrings. The list goes on and on - rucksacks, bags etc.
The very nature of a lock, is that it is constructed to hold something in position – to keep it secure and immobile. The cord lock has two positions one which allows the encased rope or cord to move freely and another that keeps it fixed.
The most typical shape for a cord lock is a small open topped barrel shape with a transverse hole. A plunger shaped part also with a transverse hole is inserted into the top of the barrel. When closed, the holes are aligned, when open it is locked and the holes are no longer aligned.
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