A wide range of wiring necessities & sundries are now available, and this includes connector strips and junction boxes. Here we have the 60A Junction Box 3 Terminal in a white finish at around 25.0mm. A very heavy duty junction box with cable capacities for each side at: 1 x 25mm or 1 x 16mm or 2 x 10mm or 3 x 6mm.
eBay