Made with a stiffened felt with Heat n Bond added to the back for a couple of reasons:1. so the glue doesn't soak through the felt2. if you use hot glue to attach the eyes, the heat from the glue activates the Heat n Bond creating an extra bond.Attaching Instructions: You can use Hot glue or a quick dry, clear, permanent fabric glue.SPECIAL NOTE: Do not iron your eyes onto your crochet or knit items as this will melt the yarn.Care instructions:Spot Clean Only with a damp clean cloth. Air Dry!! SAFETY NOTE !!NOT for use on items intended for children under 3 years old as they can be a choking hazard.Colors may differ slightly due to computer monitor configurations, photo lighting & variances in dye lots of the vinyl.