This end cap is designed specifically for Penn Elcom's R1196 series heatsink project boxes.
20-300 - Silicone Heat Sink Compound
Used for heat transfer from semiconductor devices to mounting points White Will not dry or harden 1 oz. tube
Great as always. No trouble to place order and no problems with it. It was delivered on time just as they said it would. I have ordered here several times and will continue to do so!