Its just tape...so cheap, 1 of those will last you couple years...mine last me 2 years and counting. I use tape even on my TA05R tube chassis...just wound not trust that fancy carbon fiber battery mount instead of TAPE.
Tape the bottom of the chassis first, then place battery, then tape them together, and cut off the leftover...done.
1 tape can last 3-4 packs of battery replacment...but definitely use new tape on the MAIN...just a piece of mine.