Excellent Value: Included in this bundle is a 270 Piece O-Ring assortment and a 40 Piece air conditioning valve core kit, complete with a valve core remover tool. Easy Storage: Both the O-ring and valve core containers are light latched boxes that can be packed up easily. Universal Fit: The valve core kit includes various sized valve cores that will fit many brands of cars and includes the most common R12 and R-134A valve cores. Multi-purpose: O-rings are great for many things such as plumbing, vehicle repair, or other mechanic work - Each kit comes with a helpful valve core removal tool. Plus, some of the valve cores are universal fit for tire inflation, making this an ideal set for any auto mechanic who deals with a variety of auto repair in the shop.