The item for sale are brand new aftermarket replacement straps made of the Top Grade Premium Quality Italian Genuine Calf Leather Strap with American alligator belly grain in blue color.It will fit the 21mm Cartier Santos and Tank Ronde Solo watch and it comes with finest calf leather lining at reverse side with same thickness like OEM Length: 115mm/115mm ( approx 4.5 inch )Width at Lugs: 21mm Width at Buckle: 18mm Thickness at Lugs: 5mm Thickness at Buckle :1.4mmTop Grade Genuine Premier Leather / American Alligator Grain with Heavy Duty Stitch Finest Genuine Calf Leather Lining with same color Stitch on Reverse Side These new watch strap will bring a fresh new look to your watch and will make your watch look like new.You get complete set of Genuine Leather Straps and it comes with 2 free spring bars.We carry the following size in 18mm, 20mm, 21mm, 23mm and 24mm in Black, Brown and Tan color and they are listed in our store for you to purchase.We also carry many other models of Genuine Leather Strap style and sizes for Cartier and many other models watches and those are listed in our store for you to buy.All Customers Please Read The Following Before Purchasing:Be sure to check our detailed measurement guide below or in the photos/images section of the listing to assist you with purchasing the correct parts for your watch. The guide will show you how to measure the lug width opening of your watch using a ruler, how to check your model number, and assist you with other questions you may have regarding measurement. Many watches appear the same but may be different in case size or year model. This will help to avoid any returns or exchanges. Thank you for your business!