Features: There are 6 types, 14mm for spark plug/16mm for spark plug/14mm for spark plug socket & rod/ 16mm for spark plug socket & rod/14mm for spark plug socket & wrench/16mm park plug socket & wrench, pick based on your needs. 3/8-inch Drive 14/16mm Thin Wall Magnetic Swivel for Spark Plug Socket features a 12-point design. Hardened and Heat treated Chrome Vanadium alloy steel. Constructed and Designed for Spark Plug removal and installation. Magnetic core effectively retains spark plugs and minimizes damage. Maximum flexibility in a tight area with smooth 360-degree action. Not easy to loose the plug when installing/removing, more easy and efficient for vehicle repair. Specifications: Material:Cr-V Length: 310mm/12.2in Outer diameter: 18mm/0.7in Type: 14mm for spark plug/16mm for spark plug/14mm for spark plug socket & rod/ 16mm for spark plug socket & rod/14mm for spark plug socket & wrench/16mm park plug socket & wrench(optional) Note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x for Spark Plug Socket