This is the AKA 5.5/7mm Double Ply Nut Driver.

FEATURES: 7mm driver fits metric wheel nuts on most popular 1/10 scale buggies and short course tracks 5.5mm driver can be used for shock nuts, and most nuts on 1/8 scale cars Machined aluminum handle and sleeve, steel driver

INCLUDES: Nut Driver with 7mm and 5.5mm Driver

SPECS: Total Length: 5.6" (142mm)  

BOX DIMENSIONS: 5.00" W. X 1.00" H. X 7.88" L. BOX WEIGHT: .12 LBS.