Left to right:
Koken 3771Z universal
Koken 20.8mm spark plug wrench, clip retention
Old Snap-On 13/16” (20.6mm) spark plug wrench, clip retention
Old New Britain 5/8” spark plug socket w/universal, magnetic retention
Old NAPA 13/16’ spark plug socket w/universal, magnetic retention
I pretty much use the New Britain by default. All shown for height comparison. The universal shown because maybe somebody doesn’t know about the low-height Z series.
What makes an old Snap-On liver-worthy?