Same as the butons he used to sell; it is a sticker overlay but he calls them stencils on his web site.
He still does not have the buttons already done in stock so I'll polish up the NOS ones and install the stickers.
"These buttons come in a set of two buttons. These are made using original NOS white short stem buttons that a high strength adhesive vinyl is adhered to and then sealed with a clearcoat. These came out really great and you can't beat the price i'm able to offer these at compared with what you've seen on ebay!"