Patent ID: 7819016

Claim:
An air pressure gauge comprising: a housing being hollow and comprising a base having a connecting end and an engaging end; a cover pivotally connected to the base and having a connecting end pivotally connected with the connecting end of the base with a pivotal tab integrally formed between and connected to the connecting ends of the base and the cover; and an engaging end corresponding to and detachably engaging the engaging end of the base; an engaging device mounted between the engaging ends of the base and the cover and comprising an engaging recess defined in the engaging end of the base; and an engaging tab formed on and protruding from the engaging end of the cover and having at least one engaging hook engaging the engaging recess in the base; multiple protrusions and detents mounted respectively on the base and the cover and engaging each other; and a seal mounted between the base and the cover; a circuit board mounted in the housing and provided with a power source; a pressure detector mounted in the housing and electrically connected to the circuit board; and a display mounted on the housing and electrically connected to the circuit board.