MXR M117R Flanger
A classic effect from the later 70s is definitely one of the big three of the great art of flanging, because this one - in contrast to cheaper competing products - "really flanges". Adjustable in Speed, Width, Regeneration (= feedback) and Manual (= delay time), and with that, everything that sounds good is possible: From chorus-like floating sounds to the jet plane - it has everything.
But what always resonates is the warmth of the sounds, which can not be recreated by any digital all-rounder. Those who like genuinely nice, classic flanging sounds will find it hard to look past this one.