<rant> Why are shower heads made with a circular outer section that's nigh impossible to unscrew once they get stuck with years' worth of deposits,
PS: pardon my frustration and inadequate vocabulary; coming from Belgium, I'm somewhat disappointed with construction and fixture quality in California.
instead of having a few flat faces so regular adjustable wrenches can be used?
</rant>
Anyway, what are alternatives to Vise Grip pliers or pipe wrenches for unscrewing the regular stuck round shower head pipe from the shower arm? I've tried pliers and adjustable wrenches, but obviously they slip (the ridges are a joke and the picture shows how weak the metal is). WD-40 didn't help.