This is the Pro-Start Handheld R/C Car Engine Starter from Team Associated.
FEATURES: Automatic overload cutoff protects the starter if engine is flooded
6mm hardened steel hex shaft
Can be used with any engine equipped with 6mm hex backplate
Quick release chuck for quick shaft attachment and removal
Shaft storage on side of starter
INCLUDES: Starter, hex shaft and instruction sheet
REQUIRES: Battery: 6-cell sub-C stick pack with Tamiya type standard connector,