ARRMA 1/7 Big Rock 6S 4X4 RTR Brushless Monster Truck Red is a ready-to-run Big Rock 6S built for large-scale grass, dirt, and all-terrain monster-truck bashing. It uses 6S BLX brushless power with shaft-driven 4WD and includes an aluminum chassis, center differential, and oversized monster-truck tires. Its long, planted footprint turns 6S power into stable acceleration over rough ground. Its installed Spektrum Firma 150A Smart ESC, 4074-class 2050Kv brushless motor, metal-geared steering servo, and SLT3 2.4GHz radio with AVC support 6S operation and manufacturer-rated 60+ mph performance with the specified gearing. Official dimensions: 625 mm (24.61 in) long, 465 mm (18.31 in) wide, 255 mm (10.04 in) high, with a 422 mm (16.61 in) wheelbase. Battery: Required (sold separately). Charger: Required (sold separately). Recommended power package (sold separately): 5000mAh 6S LiPo with IC5/EC5 connector, or two matched 3S 5000mAh packs where the model uses a dual lead and LiPo balance charger rated for 6S; a dual-output charger is recommended for paired packs.