This, one time use, rupture disc is designed to activate at a pressure range of 4,500 psi to 5,000 psi. It is marked 5,000 psi. It is recommended for use on DOT spec. 3A, 3AA and 3AL cylinders that have a service pressure of 3,000 psi. For use on TV series valves. ** Discontinued by manufacturer: Obsolete / No replacements: Purchase of newer valve model recommended. When existing inventory is sold, no more will be produced.