The SHERWIN DUBL CHECK PENETRANT DP-40 STEP 1 is a set of 6 automotive diagnostic service tool lubercant designed to aid in detecting leaks and issues within vehicles. Manufactured by SHERWIN, this product is specifically formulated to be effective in identifying problems in automotive systems. The penetrant formula of the DP-40 helps to reveal hidden leaks and faults, providing mechanics and car enthusiasts with a reliable solution for troubleshooting and maintenance tasks.