This is a Multiplex Brushless Power Pack for the Acromaster (MPUA2115) FEATURES: Himax HC3516-1130 Brushless Motor Multiplex MULTIcont BL-55 ESC APC 11 x 5.5E Composite Propeller Gold 3.5mm bullet connectors 4mm propeller adapter INCLUDES: One Himax HC3516-1130 motor _ One Multiplex MULTIcont BL-55 ESC One APC 11x 5.5E propeller Three female 3.5mm bullet connectors (for the ESC) Three male 3.5mm bullet connectors (installed on the motor) _ One 4mm prop adapter ESC instructions Motor instructions Hardware SPECS: BL-55 ESC Max current- 55A Volts - 15V Dimensions- 1.9" x 1.1" x 0.47" (50mm x 29mm x 12mm) _ Weight: 1.6oz (45g) Himax HC3516-1130 Motor Motor shaft size- 5mm Motor outside diameter- 35mm Mount screw thread- 4-40 tlw 8/30/07 ir/jxs upd OA 3/13/08