This is WP-SC8 RTR Sensorless Brushless ESC And 3674 4100KV 5MM Shaft Motor Combo (For 2-3S Lipo Only). Fits Arrma 1/10 Vehicle But ESC With Dean Style Plug, 5mm Size Motor Shaft And 4mm Connector. Please Note : For This System, 2-3S Only, 3S Lipo Max, Thanks. Motor Is Not Made By Hobbywing, But Is Great Motor, Motor Size Is 74mm Long, 36mm Width. Shaft Size is 5MM, Thanks. ESC Default Setting For Lipo Battery, 3S Max. Listing Include ESC, Motor And Program Card Only, Without Retail Package. Motor Limit: 2S KV? 6000. 3S LiPo: KV? 4000. Battery: 6-9 Cells NiMH, 2-3S LiPo (ESC Default Setting For Lipo Battery). Dimeter: 36mm x 74mm. Battery : 2-3S Lipo Or 6-8 Cell Nimh.