The Detex company is famous for their door access restriction and panic egress alarm hardware. While these products are designed to accept an end customer's lock cylinder (which can be a high security lock cylinder, if desired) the Detex hardware also features a battery cover lock which is not selected by the customer.
Detex hardware makes use of a very limited key series. While the "full" Detex key set runs from DT01 through DT30, not all of these keys are used anymore. This set of keys sold by Red Team Tools is DT11 through DT20. (All other keys are for legacy product lines that are no longer sold.)
The next time you see a Detex product installed on a door out in the wild, have a close look at the small wafer lock that holds the housing on to the body. You'll likely see the letters "DT" stamped on that lock along with two numbers... probably between eleven and twenty.
