Walter Lawson recommended using what he called "number 5" as valve oil. When Lawson Horns was still in Boonsboro, Md., their web site referred to it as Duralene No. 5 White Oil.
Since the usual Internet search engines did not turn up any information, I called Duralene to find out what the oil is really called. The actual name is "Duralene White Oil." The Duralene part number for a five gallon pail (the smallest amount they will sell) is 4133. Contact Duralene in Baltimore for pricing and shipping charges.
I hope this information will help those who want to follow Walter Lawson's recommendation.
Created: 19 Oct 2014