Review on Performance Tool W38154 3 Piece Extension by Mark Sharma

These are very handy for changing spark plugs in new OHC engines. They snap right onto all of my spark plug sockets. If you've done this job before, you know how frustrating it can be when an outlet gets stuck in a plug after a fresh install. The only reason I gave it 4 stars is because of the plastic button used to unlock the expansion. No problems so far, so don't let that put you off buying. This is a much better design than lock-in collar extenders which have been known to fall apart.