Wool Blend Felt Heathered 1mm thick NATIONAL NONWOVENS | eBay
Slate Gray, Thick felt – Benzie Design
FindTape FELT-06 Polyester Felt Tape [1mm thick]
Amazon.com: 40Pcs Felt Fabric Sheets - 6 x 6 Inches, 1mm Thick DIY Craft Felt in 40 Assorted Colors - Ideal for Patchwork, School Projects and Decorations (15 x 15cm)
FindTape Polyester Felt Tape [1mm thick] (FELT-06): 1 in. x 75 ft. (Black): Amazon.com: Tools & Home Improvement