"Constructed of rigid plastic. Available for either single or double pole circuit breaker lockout applications. The red color helps to identify from a distance. - CB01R is a single pole lockout and requires a switch breaker with a recessed hole in it.- CB02R is a double pole lockout that requires the breakers to be connected with a cross bar for lockout application.- CB03R is a single pole lockout that doesn't require a switch breaker with a recessed hole in it. Standard pack 6 Ea\/Bx."