There are two row designs: single-row bearings and double-row bearings. Most ball bearings are a single-row design, which means there is one row of bearing balls. This design works with radial and thrust loads. A double-row design has two rows of bearing balls. Advantages of double-row bearings as compared to single-row include that they can bear radial and axial loads in both directions. Double-row angular contact ball bearings have a steep mounting, which also can bear tilting effects. Other advantages of double-row bearings are their rigidity and compactness. Their disadvantage is they need better alignment than single-row bearings.