It’s hard to beat fabric arm caps’ durability, ease of use, and range of textile options. Look for medium- to heavy-weight fabrics that will withstand daily wear and hold their shape. Faux leathers, cotton duck, canvas, denim, velvet, and linen blends are excellent choices. If sewing your own, pre-wash the fabric to prevent later shrinking. Craft felt also works well for handmade caps but shows wear faster than woven textiles.