Hillman 10 Pack Expansion Nuts (1/4"-20 x 1") | Rubber Well Nuts with Steel Insert | Blind Hole Fasteners for Sealing Leakproof Mounting Automotive Marine Applications

DESIGNED FOR BLIND HOLE FASTENING APPLICATIONS: Ideal for blind or closed-end holes, providing secure fastening for automotive, marine, and repair applications where back access is limited. | EXPANDING RUBBER DESIGN FOR SECURE HOLD: Features a neoprene rubber body that expands when tightened, creating a firm grip and improving holding strength, reducing loosening in vibration-prone or dynamic applications. | LEAKPROOF SEALING PERFORMANCE: Expands to seal around the bolt hole, preventing water, air, or debris from passing through, ideal for moisture resistance in outdoor and enclosed installations. | 1/4"-20 COARSE THREAD COMPATIBILITY: Equipped with a steel insert featuring a standard 1/4"-20 coarse thread, ensuring compatibility with bolts and threaded rods for reliable fastening performance across various applications. | TRUSTED HILLMAN FASTENING SOLUTIONS: Hillman hardware is engineered for quality, reliable performance, and easy use in construction, repair, and home improvement. Trusted by professionals and DIYers for consistent results in everyday projects.