Biggest batteries I've found to fit in the stock XRT battery tray are these HRB 9500mah 4s 120c packs. The Lectron pro 5200's the hobby sold me are way too small. These
How to Choose a Lipo Battery For RC - GensTattu
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Freecat 1:10 Scale Large RC Cars,4WD 2.4GHz Off Road Monster RC Truck with 2 Battery 46+ KM/H Hobby Grade High Speed Remote Control Car for Adults Boys - Walmart.com
Amazon.com: HRB 2packs 4S Lipo Battery XT60 4500mAh 100C 14.8V RC Lipo Battery Compatible with RC Car RC Plane RC Truck RC Boat : Toys & Games
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