Lifejackets are a key safety feature when sailing on the sea. They differ from buoyancy jackets in a number of ways perhaps the most important being that they keep the wearers head out of the water provided the crutch strap has been secured. Important if the victim has been knocked out. Lifejackets have a number of other key features. Firstly many these days automatically inflate when they hit the water by the action of a compressed carbon dioxide cylinder situated in the folds of the lifejacket. The jackets are often brightly coloured with reflective strips and come with a whistle and an automatic flashlight to improve the chance of spotting the victim. Many now also incorporate a sprayhood to protect and prevent drowning in rough & windy conditions as well as some thermal protection to the head. In addition simple fitting with buckle fastening and provision of fixings for harnesses and lifting straps are also seen as essential these days. With care a lifejacket can have a long lifetime.