The Wheelcare Mobility Batteries can also be known as the VRLA battery. Of course, this stands for “valve regulated lead acid battery” and the two types are virtually the same battery. So,the AGM battery is sealed unit and will not spill out any acid, even if the Wheelcare Batteries are fitted on their sides, the acid will not leak. This is because the acid is not free flowing, but is filled with a type of glass matting. Hence the term AGM “absorbed glass matting”. By adding this glass fibre, then the fisher price toy car batteries increased surface area gives them more power when compared with a standard 12 volt battery that we use on many of our cars.