Loved it,made it effortless to install spark plugsAppears to be well-built and firmly grasps the spark plug. Unlike the plastic grommet versions of this tool, this doesn't look like it will wear out and lose its "grippiness". It is surprisingly small compared to my other spark plug sockets. As has been said elsewhere, be sure to use a quality locking extension on this socket. My favorite are the ones from S-K Tools - they are expensive, Amazon doesn't appear to carry them, but the spark plug socket *won't* come off the end! Don't cheap out on the extensions because I have a feeling this socket will stay firmly attached to the spark plug if the extension doesn't lock well.Update after actually using the socket:Worked as expected - firmly gripped the spark plugs and came off easily after the plugs were torqued to spec. It goes without saying that you should use a torque wrench to install plugs! I pulled this Mini Cooper's plugs at more or less the recommended servicing interval (60,000 miles) only to find that they were pretty badly eroded. If you are dealing with a Mini that has driveability complaints (hesitation, misses, etc.) definitely consider the plugs if the mileage is 30,000+ and they haven't been changed.Fits perfectly into the well and is made with good quality material, Just as good as oem , without OEM price!Wouldn't use anything else to avoid risk of not fitting when i have the engine all opened up! Product worked flawlessly on my Bosch spark plug change out. The inside has 5 or so metal tongs that grab onto your plug, unlike traditional rubber boot. This was an excellent design and worked perfect. I'd recommend this product as the quality was excellent for the price. Normally wouldn't bother to review socket but this is the spiffiest plug socket I've ever used. All the plug sockets I've used in the past were the rubber ring type which work fine until the ring starts pulling out of the socket.This was for my 2008 E92 BMW 335xi - N54 engine - fits perfectlyIt is perfect for the 340i any drive type, and any car using the B58 engine. Fast shipping. Cannot say how it has held up used for one plug change, but if you only do one plug change every 5 years it will last you a lifetime I imagine.Its fit perfectly and easy to handleSpark plug socket worked great on a 135i N55 engine. The mechanical fingers to secure the spark plug in place do a great job of securing the spark plug in place for either installing or removing a plug. I did run into the scenario, when installing a new plug, where these fingers gripped the plug I was installing with a greater force than the socket was secured into 3/8" socket extension causing the socket to detach from the extension (and remain in my engine) but after reconnecting the extension into the Caldera socket I was able to decouple the socket from the spark plug and remove the socket from my car's engine.Overall a great product that worked as advertised.Great for the n54! It holds the plug just tight enough where it will not fall out but it will stay in while installing a new plug.I needed to replace the spark plugs in my 2012 BMW 328i (F30) with the N20/N26 2.0L engine, and this socket worked perfectly. The internal spring retainers hold the plug with just the right amount of tension. The socket's teeth fit the BMW/NGK plugs perfectly, and the square drive hole mated firmly with my extensions and ratchet. As far as I can tell, this socket is exactly the same as the OEM socket made by BMW (part # 83300495560), except the Caldera socket has a much nicer chrome finish and is less than 1/3rd the price of the OEM socket. I highly recommend this socket!Flexible enough but you lose a lot of torque. Could not use it to remove the spark plugs from my engine.