This is the Factory Team 2.5mm Ball Driver Bit from Associated.

FEATURES: Fits 1/4" driver handle Steel construction

INCLUDES: 2.5mm Ball Driver Bit

REQUIRES: Installing in handle

SPECS: Length: 2.9" (75mm) Ball Driver Size: 2.5mm  

BOX DIMENSIONS: 3.00" W. X .25" H. X 3.25" L. BOX WEIGHT: .02 LBS.