HPI Blitz battery spacer set
New from HPI, use this convenient battery spacer set in your Blitz short course truck to fit the larger 3S, 11.1 volt battery packs for extra power and maximum top speed. This set includes spacers and extra-long hardware to fit most hard-case 3S LiPo batteries in any HPI Blitz truck.
Source: HPI [hpiracing.com]