The shorter version accommodates the newer Burn-e models where the battery is self-enclosed in aluminium casing. This box does not enclose the battery. The box sits in front of the battery and encloses the main cables and converter. The fuses sit between the box and the battery. The newer aluminium battery with shorter battery box is shown in this video from Michael Sha.
The longer version accommodates the older Burn-e models where the battery is not self-enclosed in aluminium casing and therefore requires the box to provide protection of the battery. This box extends the shorter version (for the battery) and is 510mm in length.
Typically required if original box is physically damaged.
Suits NUTT A5-D 2-piston calliper on early NAMI Burn-e, MUKUTA 10+, Limited models of Zero 10X/11X, Dragon Hunter X11, early Dragon Cyclone Pro & early VSETT and 4-piston callipers NUTT Y-5 & TurboBrake HB427-4M.