This is an Engel kit, but heavily modified. The deck was replaced with 2mm polycarbonate and slots cut with a slotting tool on a lathe/drill. There are 3 access hatches instead of the original 1. The internal layout was completely revised. The dive system is the Engel Tmax that works very well. There are too many other changes to mention, but suffice to say they were to make the submarine more realistic and also easier to maintain. (Motor: Mabuchi 550) (ESC: MTroniks 20A) (9/10)