3/8"SD Spark Plug Sockets From Britool Hallmark 16mm & 21mm

The Britool Hallmark 3/8" square drive spark plug socket is designed for reliable performance and ease of use in automotive applications. Finished in high polished chrome, it offers excellent durability and corrosion resistance while maintaining a professional appearance.

Stamped with the modern Britool Hallmark Marque of Skill branding, this socket reflects trusted quality and precision engineering. Its hexagon profile ensures a secure fit on spark plugs, allowing for effective removal and installation.

Available in two metric sizes, 16mm and 21mm, the sockets are designed for versatility in use. The 16mm version has an approximate overall length of 63mm and can be used with a 3/8" square drive ratchet or a 19mm spanner. The 21mm version measures approximately 65mm in length and is compatible with a 3/8" square drive ratchet or a 22mm spanner, providing flexibility depending on access and working conditions.

Also available as a magnetic version is required - MMSP

Please note picture is for illustration purposes only. The size shown maybe a different size but you will receive the size you order.

The HALLMARK range was developed by Britool in the 80's for the automotive aftermarket. it has been the professional’s choice ever since. Each tool is marked with the Britool hallmark  your guarantee of quality.

The Britool Hallmark guarantee covers against defective materials and/or workmanship when used for the purpose for which they were designed and for the expected life of the tool. In the unlikely event that a product fails during normal use, it will be repaired or replaced. The guarantee does not extend to fair wear & tear, moving parts such as ratchet mechanisms or consumable items such as bits and repair kits.