Dekorman 300 sq. ft. 3-15/16 ft. x 76-1/5 ft. x 6 mil Blue Virgin Polyethylene Moisture Barrier and Vapor Barrier Underlayment DKM-6MB-300 - The Home Depot
FLOORLOT BlueStep Underlayment with Moisture Barrier for Laminate and Wood Floors, (200 sq.ft Roll) - Amazon.com
Tiny House Subfloor & Vapor Barrier (Ep.8) - YouTube
CalFlor VaporBlock 150 sq. ft. 6 ft. x 25 ft. x 0.006 in. Polyethylene Vapor Barrier Underlayment for Hardwood Laminate Floors GA60240M - The Home Depot