Homeowners dealing with sticky or noisy sliding patio doors - this Slide-Co roller assembly might be your solution! These heavy-duty rollers feature 1-1/4 inch steel wheels with ball bearings that make your door glide smoothly and quietly. The housing is made from solid steel and is height-adjustable, measuring 11/16 inches thick with mounting tabs spaced 5-3/4 inches center to center. The minimum collapsed height is 1-1/2 inches, and the tandem-style wheels have concaved edges that grip the track perfectly. These are designed specifically for sliding patio doors that run on single raised aluminum or steel tracks. Just a heads up - you'll need two of these assemblies per door (this package contains one), and installation fasteners aren't included. But if your door is sagging, hard to open, or making grinding noises, replacing the rollers can make it feel like new again. The steel construction ensures long-lasting performance, and the ball bearings provide that smooth operation you remember from when your door was first installed. DIY installation is pretty straightforward if you're handy, or perfect for your repair person to install quickly. No more struggling with stubborn patio doors - these rollers restore that easy, smooth sliding action you've been missing!