Premier Spark Plug Socket 3 / 8″Sq Drive 21mm

• One of a comprehensive range of Premier Hand Tools, suitable for daily professional use.
• Hardened and tempered Chrome Vanadium steel socket.
• Fully polished mirror finish with knurled ring.
• Socket insert grips ceramic insulation and assists in extraction of plug.
• Especially useful on deep-seated plugs.
• Lifetime guarantee*.