NIBCO 3/8"" Copper Tube Cap Nibco 61738 NIBCO 3/8"" Copper Tube Cap
Nibco 61738 This is a NIBCO 3/8"" Copper Tube Cap Nibco 61738. This tube cap is made of copper and is 3/8"" in diameter. It is a replacement tube cap for the NIBCO 61738 fountain pen.