Redesigned and improved battery cap compatible with the PEQ2 and PEQ2A devices. Features more aggressive knurling on the outside. Internal spring can easily be replaced with existing off the shelf springs in case of severe corrosion. Internally installed O ring to keep the compartment sealed. 
 
This is the PEQ2A style battery cap. Old school PEQ2 caps look different from this design and lack the internal spring. Coming soon.