This heat shrink tubing, designed for 26700 cylindrical battery assembly, provides reliable insulation and mechanical protection for research-grade energy materials and pouch-type cells. With a thickness of 0.08 mm and a folding diameter of 42 mm, the tubing fits snugly over standard 26700 cell bodies after heat application, ensuring consistent coverage and electrical safety. Each 80 mm length segment accommodates typical cell height requirements, and the 100-piece pack supports repeated experimental setups. Commonly used in battery prototyping, electrode isolation, and device-level assembly, this accessory simplifies secondary packaging without introducing significant volume or weight. The material's shrink ratio and durability allow it to withstand moderate handling during testing, making it suitable for both academic and industrial R&D environments where consistent, clean insulation is critical.