The Mansfield Bone Lid Only for 3185 Model 3185LID-BONE is a Bone 18?x10?. The Mansfield Bone Lid only for 3185 Model 3185LID-BONE weighs about 8lb, and is made of a vitreous china with stunning beveled edges. The Mansfield Bone Lid Only for 3185 Model 3185LID-BONE comes with a limited Mansfield lifetime warranty. Mansfield is an American company that?s been in business since 1929, and has been one of the top producers in design, and quality for the past 80 years. They are the largest domestic producer of sanitary ware, and strive to ensure you get the best products available.