I purchased this new, but I'm selling it because I'm using a different collar. It's the popular Blue Dusk color. Please see below for size details. This collar uses reflective thread. It's lightweight and features a durable plastic buckle. 【Materials】(Tape) Polyester, (V-ring) Aluminum alloy 【Weight】45g (M) 【Color】Blue Dusk (BLDK) 【Size】36-51 【Tape Width】(M/L) 25mm 【Neck Size】(M) 36-51cm 【Suitable Weight】Up to 25kg Retail Price: 4400 yen Although it's new and unused, it's been stored at home by a private individual, so please refrain from purchasing if you are sensitive to such things or are seeking a perfect item.