The plastic isn't thick down at the bottom so I was scared to try to twist the battery. I'm also not sure how strong the switch assembly is so I opted not to put a screwdriver in between the switch and battery to try and pry it out. Instead I used a pair of needle nose pliers to grab the end of the battery firmly near the tip, then a second pair to wedge between the bottom of the plastic and the other pair of pliers to put pressure on the bottom of the plastic to pry out the battery. It wasn't very difficult. There appears to be some sticky adhesive inside the nock to help hold the battery, though none was on the battery once I had it out.
Inserting the fresh CR425 battery was far easier than with a Lumenok. It simply presses into the base of the nock. If you press the battery in too far, you'll turn on the nock. Just turn off the nock to get the battery at the correct position. Fortunately, the force of a shot will also help seat the battery so it's a fairly foolproof design.
