One-step marking with easily interchangeable letter & numbers.Character Capacity 8.Made of high shock alloy steel.Unique locking bar prevents type from incorrect insertion.Allows for marking one line of characters into various industrial products.Package - bagged.Made of high shock alloy steel.Most durable steel type holders on the market.Easily interchangeable letters and numbers.Save time and money with one step marking.Steel type not included unless purchased as a kit. Proudly made in the USA.