Karcher Universal Wash Brush Attachment Kit for Electric and Gas Power Pressure Washers The Karcher Promise: Cleaner. Quicker Karcher Universal Wash Brush: Incoming water causes inner brushes to rotate. 4000 PSI & 4.00 GPM Rating Karcher Soft-Bristle Wash Brush: Extra soft synthetic bristles for gentle surfaces and applications. 3000 PSI & 4.00 GPM Rating 1/4-inch Quick Connection Fits Karcher residential gas & electric pressure washers and most brands residential pressure washers Includes adaptors for Karcher bayonet and threaded connections