This is the V540 Brushless 18.5T Rock Crawler Motor from Venom.

FEATURES:
Vented alloy heat sink to reduce unwanted heat build-up and increase longevity
          Pre-wired bullet plugs
          Factory installed capacitors
          Dual ball bearings
          High power brushes

INCLUDES: One Venom 18.5T Brushkless Rock Crawler Motor

REQUIRES: ESC designed for rock crawler

SPECS:Can Length: 53mm (2.09")
          Can Diameter: 36mm (1.42")
          Shaft Length: 10mm (0.39")
          Shaft Diameter: 3mm (0.12")