Terminal/connection box, 500 volts, 3 phase, 2 circuit, for two (2) 3 conductor cables up to 250 MCM, submersible to 15 feet, non-magnetic. Consists of 3 bus bar weldments mounted on a laminated plastic (GME) insulator secured to the bottom of a 12 x 13 enclosure per MIL-E-24142/6. The cables are clamped between a fixed and moveable cap which have grooves cut in them to keep the cable in place. The groove is sized for a maximum cable size of 250 MCM. Larger cable sizes can be accommodated by increasing the size of the groove which also changes the Symbol number. Symbol 418.2 accommodates cables up to 300 MCM. Symbol 418.3 accommodates up to 400 MCM. Part number M24558/25-418.1 per MIL-T-24558/25. NSN 5940-00-216-7409 applies to the Symbol 418.1 which is the only NSN assigned to this group.