Review on Caldera Thin Wall Spark Plug Socket 12-Point, 14-mm: Ultra-Fit Solution for Precise Spark Plug Work by Matt Jenkins

Worked great for changing the spark plugs on my N55 BMW F10. Instead of the traditional rubber used to grip the plug port, the Caldera features metal finger grommets that grip the port. Sometimes the rubbers can be so tight that the ratchet extension pulls out of the socket - no problem with this metal tongue design - the socket pulls away from the plug immediately after installation.