This is a 7 mil, yellow, varnished coated cotton cloth without an adhesive.
From the Manufacturer
Scotch® Electrical Insulating Varnished Cambric Tape 2510 insulates and seals electrical components. Resistant to punctures and cut-through, the straight cut woven cotton cambric fabric maintains its insulating properties through normal wear and tear. This varnished tape comes without adhesive, which allows for a clean re-entry to connections. Flexibility offers ease of installation and moisture resistance protects electrical connections. Cambric tape is often used for insulating joints requiring rapid and clean re-entry such as motor leads and service drops. Operating temperature range is 32°F (0°C) to 220°F (105°C).
This 7-mil thick, yellow varnished electrical tape is rated for Class A 220°F (105°C) applications. Typical tensile strength is rated for 50 lbs/inch.
For more than a century, 3M™ has applied innovation and technology to improving our customers’ lives and supporting their business goals. Today the company, from its headquarters in St. Paul, Minnesota, serves industrial and commercial customers and consumers in nearly 200 countries. 3M™ electrical products for industrial, commercial and residential construction and maintenance include electrical insulators, connectors, splices, terminations, terminals, fire-resistant tapes, cable ties, portable labelers, and diagnostic and detection products. The 3M™ brand, across thousands of products, represents consistency, superior quality, and value.