Recently I purchased a Luminous Emergency Hammer and Seatbelt Cutter. This looks like a toy plastic hammer, but is a serious tool for escaping from a crashed car. The hammer has a sharp steel point designed to break a car side window (similar hammers are fitted to some buses). There is a blade in a slot in the handle to cut a seatbelt.
The hammer is intended to be mounted in a car, within reach of the driver. It should be noted if the seatbelt locks in an accident, the driver's reach will be very limited. The black plastic mounting bracket the hammer comes with has holes for bolting in place, but it also has four sharpened steel prongs which can be pushed through the carpet lining the passenger compartment of the car to fix it in place.
As all the lighting in a car may fail in an accident, the mounting bracket for the hammer has a luminous dot. The hammers are usually Safety Orange to make them easy to see in low light. The hammer I selected is yellow and the whole handle is made of glow-in-the-dark plastic, making it easy to find.
The hammer looks solidly built, with three steel bolts holding the two parts of the handle together. The seatbelt cutter is recessed so that a finger will not fit in the slot to be cut. The hammer has only a small amount of steel in the head and so is less heavy that a carpenter's hammer. The mounting bracket appears to hold the hammer firmly, but obvious it should not be positioned so it could fly forward in an accident and injure a passenger.