About K&W

K&W has delivered the best DIY leak solutions since 1938 when it introduced Permanent Metallic™ Block Seal, one of the first coolant additives to provide permanent repair.
Today the K&W lineup includes a range of stop leak solutions as well as repair and maintenance products that help drivers get more miles from their cars.
From head gaskets and engine blocks to automatic transmissions and power steering, K&W stop leak products are affordable and effective alternatives to costly repairs and parts replacements.

K&W – Stop Leaks… Start Driving!™

Our Other Brands


Mary Kate Marine Products

CRC Smart Washer