Extension Ring,Square,22.5 cu. Electrical Box, Square Extension Ring, Capacity 22.5 Cu-In, Material of Construction Steel, No of 1/2" Side Knockouts 8, No of 3/4" Side Knockouts 4, Depth 1 1/2 In, Length 4 In, Width 4 In, Standards UL 514-A Listed, File E195978.
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