Dual use - these wheels can be locked for fixed wheel or unlocked for a swivel wheel. Designed to fit most walkers they offer superior strength while remaining lightweight and easy to use. Special package includes our exclusive Top Glides FlexFit Universal Ski Glides which are durable, quick to install, and perform well on most surfaces. With 5-inch wheels and 5 height adjustments these wheels are a smart and versatile choice. Satisfaction guaranteed or your money back.