This is a 2cm wide half-check collar for medium-sized dogs. It's adjustable, but please consider this size as a general guideline. **Please note that the size refers to the head circumference, not the neck circumference.** This is a one-of-a-kind finished product. If you need a different size, please contact us. Leather width: 2cm Thickness: Approximately 4mm (may vary slightly depending on the leather) Head circumference: 34cm (at the hole position in the photo) ● Leather part size: Approximately 25cm ● Chain size: Approximately 12cm (The total length may not equal the ordered head circumference due to the overlap of the chain and leather, and is calculated to allow the collar to be put on and taken off over the head.) Please contact us if you have any questions. +++++++About Extra+Heavy+++++++ Extra+Heavy is a handmade collar shop specializing in custom-sized collars, including half-check collars and leads, mainly for bulky breeds like bulldogs and long-necked dogs like Italian Greyhounds. We have shops on Rakuten, Yahoo! Shopping, and our main store. Search "エクストラヘビー" (Extra Heavy) on Google Maps. * You can find Extra+Heavy by searching "首輪 スタッズ" (collar studs) on Rakuten and Yahoo! Shopping malls.