For sport and aerobatic models weighing 2-6 lbs. The XTRM 2820/06 is a 1000 KV Brushless Outrunner with a current capacity of 37 amps @ 60 seconds. A maximum efficiency of 82%, a no load current @ 10vdc of 2 amps and an internal resistance of 59 Mohms. This outrunner has a 4mm shaft and is designed to run on 8-14 NiCad/NiMH cells or 3-5 LiPo cells. A 11x6 prop on 3 cells or a 10x5 on 4 cells is great for all around sport and aerobatic flying. Includes Radial Mount, 4mm Collet type prop adapter and 3.5mm Gold Plated Bullet Connectors. This motor weighs 5.1 oz. and the dimensions are 35 x 45mm.