Easily restore smooth and reliable operation to your patio or sliding glass door with this Prime-Line D 1876 Sliding Door Roller Tandem Assembly. Designed as a replacement for worn, damaged, or missing rollers, this assembly helps extend the life of your door and improve its performance. It is commonly used by a variety of patio door manufacturers, making it a versatile repair solution for homeowners and DIY installers.The roller assembly features a durable stamped steel housing with a protective yellow zinc finish that resists wear and corrosion. Inside the housing are tandem concave steel ball bearing rollers, each measuring 1-1/2 inches in diameter by 5/16 inch thick. These rollers are engineered to provide smooth gliding action, reduce door sticking, and ensure long-lasting performance.The housing measures 11/16 inch wide, 1-3/16 inches tall, and 4-5/8 inches long, with a minimum collapsed height of 1-1/2 inches. Installation and height adjustments can be made with a standard Phillips head screwdriver, making it a straightforward project for most DIY homeowners. Whether you are repairing a sliding patio door for the first time or maintaining an older unit, this roller assembly is designed for strength, durability, and ease of installation.