When working at heights or in hazardous situations, workers can sometimes drop their tools, potentially causing serious injury to workers below as well as reducing on-the-job working time.Originally, the carabiner was used in certain situations or sports activities where ropes were involved, such as rock climbing, sailing and mountaineering, however carabiners are now widely used by many individuals and in many different situations. They are ideal for using across a wide range of industries and applications such as construction, roofing, maintenance, telecommunications and general industry.A tool lanyard or tool holder can be attached to a workers waist belt and then tools can be attached using the carabiner or by looping the cord tightly around the tool to ensure it is secure.The carabiner is made from a variety of materials such as aluminium, steel, nylon, stainless steel, polyester and plastic. It is available in different sizes, depending upon your requirements. It has a spring loaded clip or a screw lock which you can easily attach to your tools.There are various types of carabiners, the most distinguishing difference being the shape and design, each one operates a little differently. Oval are most basic and allow the transfer of equal weight. D asymmetric shape also known as an offset D are the strongest and most durable and allow the majority of weight to be transferred to the spine of the carabiner, these are the ones most climbers use for climbing activities. A D-shaped carabiner allows for a wider gate opening, which makes clipping them easier. A pear shaped, also known as HMS type are the easiest to use, as the gate on these HMS types can open wider than other carabiners, sometimes HMS will be marked on the carabiner to make them easily identifiable.There are also different types of locking mechanisms on carabiners, some are auto-locking or self-locking which lock when the gate is closed and others are manual locking, known as a screw-lock or screw gate, where the user is required to manually screw the sleeve into the gate to lock it. Non-locking carabiners have a sprung gate that will snap back into place once opened.