NQEUEPN 4pcs M22-15mm to 1/4in Pressure Washer Adapter Set, Power Washer Adapter to 1/4in Fast Connect & Quick Disconnect Pressure Washer Fast Connector Kit for Power Washer Hose Pump 5000 PSI

I used https://a.co/d/0tqaNfs from the OP with a similar 2x11 O-Ring and still saw some leakage from the wand end. However I resolved it by switching to a slightly larger/thicker 7/16" x 3/32" (11.1 x2.38) o-ring.