White cold-rolled steel spacer for cold-rolled Smoke Detector Protector series adds 50mm (2") to depth of cover and has knockout for mounting around exposed conduit.
STI-8201-W
White cold-rolled steel spacer for cold-rolled Smoke Detector Protector series adds 50mm (2") to depth of cover and has knockout for mounting around exposed conduit.
If this isn't the specific item you are looking for, explore similar models from this same product series.