ETA - Maintenance Kit
Fits 3520. Service Kit includes: Jet nipples--0.32 (LP Gas), 0.28 (White Gas), 0.22 (Kerosene). O-Ring, Leather grease, Leather gasket-for pump, 2-Priming Pads, Burner holder.
Contains brass that can expose you to lead, a chemical known to the State of California to cause cancer, and birth defects or other reproductive harm. - P65Warnings.ca.gov