Electrical underground splice boxes protect and organize buried wiring connections, helping ensure safe, durable power delivery in outdoor and subterranean environments. This guide showcases five reliable options, highlighting design features, materials, and installation. 【Built for Underground Electrical Splicing】 Designed as an Electrical Junction Boxes / pull box Ideal for buried electrical connections, low-voltage wiring, landscape lighting, CCTV, and telecom applications where organized cable access and future inspection are required. Unlike an indoor splice protected by a simple junction box, an underground repair requires a connection that is. Underground splice on 12/2 UF wire on a 20amp GFCI Protected circuit. I go over the process to make a.