Specifications:
 Dimension: 37mm x 56mm, 76mm(with shaft)
Weight: 193g (kv1600) (including connectors)
Voltage: 3-6S 
 Max current: 55A 
 Diameter of shaft: 5mm 
Length of front shaft: 20mm
ESC: 65A 
A not-so serious upgrade for 500 class helis. Solid performance, and a perfect motor for first time 500 heli pilots.