See: Modelix Racing

Modelix Racing have added two new 6.6V 2500mAh LiFe receiver batteries to the Ultimate Racing range. Available in flat or hump pack configuration, they are designed to power the electronics of 1/10 & 1/8 Nitro Cars. With standard dimensions, the RX-Packs are suitable for most R/C models available on the market that require flat receiver battery packs like Mugen, Associated, or hump receiver battery packs like Kyosho, etc…