Standard for brochure interiors, high-quality flyers, and catalogs.
While usually referring to paper weight, "JDW 70" can also appear in other niche contexts: JRV Decoupage Paper - Mama Bear Blue Jdw 70
It is more substantial than standard copy paper (which is usually 20 lb or 24 lb) but thinner and more flexible than cardstock. Standard for brochure interiors