3-3/4" ID Torsion Springs w/ Cones - Commercial, Heavy-Duty, High Cycle

3 3/4" (3.75" Inch) Inside Diameter Commercial Torsion Spring with installed Cones Commercial Torsion Spring with Cones – Engineered for Heavy Doors, Continuous Operation & Long Service Life Designed for demanding commercial and industrial applications, this heavy-duty torsion spring delivers smooth, reliable operation for large overhead doors in high-traffic environments. Made from durable oil-tempered steel, it is built to handle frequent daily cycles while providing long-lasting performance and reduced downtime. This spring includes pre-installed stationary and winding cones for secure installation and balanced door operation. Fits standard 1" shaft sizes. Key Features: • Fits Standard 1" or 1.25" Keyed Shaft Size (Depending on Selection) • Pre-Installed Stationary & Winding Cones (3 3/4" ID / 3.75") • Heavy-Duty Oil-Tempered Steel Construction • Designed for Continuous, High-Cycle Operation • Ideal for Heavy Commercial & Industrial Doors • Smooth, Reliable Performance for High-Traffic Applications • Made in USA Perfect For: • Warehouses • Industrial buildings • Auto shops • Commercial overhead, sectional, and rolling doors ⚠️ Safety Warning: Torsion springs are under extreme tension and can cause serious injury if improperly handled. Installation should only be performed by trained professionals using proper tools and safety procedures.