From Bitspower, the multi-transfer base, part # BP-WTP-C03, is a shining silver female BSPP 1/4" to female BSPP 1/4" adapter. Simply put, it allows for connecting two BSPP threaded fittings to one another, as shown in our second thumbnail image.
True Hi-Flow Design.
Hi-Quality Brass Material.
High Durability Nickel Finished In Silver Shining Color.
Design For Dual IG1/4" Application.
Thread : Inner G1/4"
Thread Length : 5MM