This oil filter cap wrench is perfect: 3/8 rear opening set in reinforced plate - just right for your 3/8 ratchet or breaker bar. Definitely a heavy duty / quality piece.I will be using it on Fram 7317 spin-on oil filters (XG7317 in my case) - for that last half turn or so, and to loosen the filter if it does not want to loosen easily when changed.I measure the back side of my Fram XG7317 as 65.5 mm - and this filter wrench (with its slight taper to accommodate 65 - 67 mm filters) truly fits like a glove; no slip whatever.Highly recommended.
Rating: [5 of 5 Stars!]