if you use a surefire x300/x300u light the Bawidamann Gotham is a good IWB option...
+1. For a holster: I had a custom kydex iwb holster made for this setup by Multiholsters. It’s perfect, up to their usual quality. It even has a small dent in one side where the creator pressed a thumbnail into the warm kydex to make the retention absolutely perfect. Hand-finished /fitted.
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