This is a pair of Milgard patio door wheels for the Tuscany and Classic Series patio doors. These wheels only fit the Standard Rail patio door, which is also known as the Narrow Rail patio door. The Milgard Tuscany & Classic French Rail sliding doors use a different shaped wheel, which we also sell on Amazon. These are OEM parts directly from the Milgard factory, so they will be a perfect fit. The rollers are made of stainless steel and have a very long lifespan. Most orders will be shipped within 2 business days.