HEM/Rogy single pole (1 pole width) RCBO (RCD), Type A, 6kA, 30mA. Available in 10, 16, 20 and 32 amp ratings, these devices combine earth leakage and over-current protection - circuit breaker and RCD in one device.
These are ideal where a single circuit* needs protection against short circuit (fused) as well as earth leakage (RCD) protection. Confusingly, although they are termed "single pole" this relates to the width of the device, the wiring is double pole (phase & neutral).
* If more than one circuit requires RCD protection and there is space in the switchboard it is sometimes better value to use the double pole 63 amp rated RCCB (RCD) devices - these can give earth leakage protection for up to 3 circuit breakers, although extra labour is required to fit.