This is a holder for storing the master controller key used on trains. Material: Stainless steel Handmade product Spring-loaded, push-in type Please note that the master controller key is not included. Please be aware that the ring shape may vary. We only sell on Mercari and Yahoo Auctions, so please be careful of products that use images from other online stores. We also have direct sales, so we may delete the listing when the stock runs out. If you would like to purchase multiple units, please let us know in the comments. We will list the desired number of units and offer a discount on the shipping cost. We do not offer any other discounts, including the desired price.