Two LARGE BORE to standard bore tire valve adaptors. These adapt large bore OTR tire valves down to standard bore so that regular common air chucks and tire gauges can be used. This type screws into the valve core threads of a large bore valve. It has a gasket that seals against the end of the large bore valve and a plunger that depresses and opens the large bore core when a chuck or gauge is used. This type is far better than the ones that screw over the external cap threads. The problem with that type is the cap threads are always corroded or damaged and they won't screw on. That type also seizes on the end of the valve. Large bore valves are used on some OTR or off the road industrial and mining tires. They can be found on dirt scrapers, bucket loaders, road graders, large agricultural flotation tires, mining equipment, etc.