The RCA-2C is our second best selling RCA plug. With it's machined, one piece body and pure copper center pin, it can be used on the finest interconnect cables. We use it with out BL-1 interconnect. The cable entry hole of the RCA-2C is 6.0mm, allowing it to comfortably accept cables up to 5.6mm. A set screw under the barrel provides dependable strain relief.