RS Berkeley Baritone Horn Valve Oil 5 Pack w/Bari Horn Cleaning Cloth Package includes valve oil 5 Pack with 1 cleaning cloth. Valve oil: RS Berkeley Valve Oil is an ideal lubricant for trumpets, trombones, and all brass valve instruments. This Pro Strength formula provides long lasting, fast valve action. RS Berkeley Musical products are endorsed by numerous leading players and repair techs and used by beginners, pros, & educators alike. Microfiber cleaning cloth provides easy cleaning; removes dust, dirt, smudges, and fingerprints.