I guess they are referring to Lead Vent and Pipe Flashing - Lead

https://www.lowes.com/pd/Mayco-Industries-Inc-3-in-x-10-in-Lead-Vent-and-Pipe-Flashing/3714020?cm_mmc=shp-_-c-_-prd-_-bdm-_-ggl-_-LIA_BDM_103_Roofing-Gutters-_-3714020-_-0-_-0-_-0&ds_rl=1286981&gclid=Cj0KCQjwqp-LBhDQARIsAO0a6aK7rKQ-TgZCy8dFFTUzdyztqZYfaubLdVkQO6ObigkQWVSmzK29aB8aAoQjEALw_wcB&gclsrc=aw.ds