Snap-On STSM16E is a 1/2" drive metric 16mm standard triple square bit socket driver. The socket type is standard and the drive type is triple square. It is a single item and not a custom bundle. The drive size is 1/2in. and the surface finish is chrome. The system of measurement is specialty metric. The manufacturer part number is STSM16E and the brand is Snap-on. The tool is made in the United States and is included in the Sockets category of Automotive Tools & Supplies on eBay Motors.