AstroFlight 549 Blinky to Thunder Power Adapt This is the Astro Flight "Blinky" Balancer for Thunder Power Batteries.Features: This Battery Balancer is designed for use with LiPo batteriesAccepts one to five cell Thunder Power, Apex and other battery packs with 2mm connectorsIncludes: One Astro Flight "Blinky" balancer for Thunder Power batteries and one instruction sheet