Glossary

ASL
The Acceptable Suppliers List of those manufacturers of snap fasteners who have proven that their products are manufactured to the standards as set forth in specification MIL-DTL-10884. Scovill’s DOT® products conform to stringent US Military and Commercial specifications, are Berry Amendment compliant (USC, Title 10, Section 2533a), can be identified by our registered CAGE Code and are proudly made in the USA.
Attachment
The fastener segment, component, or unit physically affixed to the application which could include materials such as fabric, canvas, vinyl, etc.
Back Plate
A metal stamping that is used to help affix certain closure products to the application. It is also another word for a washer.
Bench Press
A hand-operated attaching machine, that when equipped with the proper chucks and dies, is used to make a snap fastener attachment. Typical bench press styles employ lever type actions and make one-segment (male or female) attachments at a time.
Button
Another term for the cap component of the standard snap fastener closure.
Cap
One segment of the female half of the snap closure. The cap serves two functions; securing the socket to the application and providing style options. The cap is round and designed with a tubular component that is used to secure the socket to the application.
Chuck
The chuck is the upper tool in a bench or foot press. The chuck is designed to hold the fastener in place through the attaching process, while contributing to the attachment by rolling, crimping, or supplying other actions according to the design of the chuck.
Clinch Plate
A washer type product used with pronged mating parts generally of the curtain (Lift-the-DOT®®) and turn button (Common Sense®) types of snap fastener closures.
Closure
A device or group of devices that in their interaction provide a closing and opening function at the discretion of the user on an application.
Curtain Fastener
A generic term used to describe a fastener type that is so designed as to snap and unsnap in one direction only. The original application was to secure canvas side curtains on horse drawn carriages, so curtain fasteners snap and unsnap in one direction only. Curtain fasteners are actually Lift-the-DOT®® fasteners and the key feature of this product type is that it locks on three sides only releasing on the fourth side.
Die
A die is the lower tool in a bench or foot press. The die holds the fastener in place through the attaching process and accepts the force of the attachment while providing a stable base.
Eyelet
An eyelet is a tubular part that is used to secure a stud or socket to the application. The basic design of the eyelet is similar in appearance and function to the tubular component as described in the cap definition.
Eyelet Curl
An eyelet curl is the result of the controlled rolling of the eyelet barrel through the attaching process back onto itself, resulting in a doughnut shaped rim greater in area than the diameter of the stud or socket hole that the eyelet is attaching itself to. During the curl the base application material is sufficiently compressed to affect a tight, secure attachment.
Female
A female is the socket and cap segment of a snap fastener closure that engages the stud and forms the complete closure.
Foot Press
A manual attaching machine that is foot operated and employs a toggle action. When equipped with the proper punches and dies, the press is capable of attaching snap fasteners. Typical machines make one-fastener segment attachments at a time.
Gypsy Stud
A gypsy stud is a stud that incorporates an eyelet in its design that allows the user to make back-to-back attachments with either a socket or stud attached to the eyelet component of the gypsy stud.
Ligne Size
Snap fastener cap diameters are measured in terms of ligne sizes. A ligne (pronounced line) is a historical unit of measurement typically used by apparel button manufacturers to identify the diameter of buttons. A ligne equals .025 inches and there are 40 lignes to the inch. A 24-ligne cap for example is .600 in diameter.
Male
A male is the stud and eyelet portion of a snap fastener closure. The stud engages the socket (female) to form the complete closure.
MIL-DTL-10884
MIL-10884 is the U.S. Government specification for snap fasteners.
Murphy Fastener
A Murphy fastener is a dated generic term for the Common Sense® turn button fastener.
Post
A post is another term for an eyelet.
Pronged Eyelet
A pronged eyelet is an eyelet product that incorporates in its design, prongs (legs) that are used to attach the eyelet to the application.
Punch
A punch is the upper tool in a bench, hand or foot press. The punch controls the upper fastener as it engages with the fastener on the lower die.
Reversible Stud (Low Shelf Stud)
A reversible stud is a stud with a low inside shelf height that allows it to be used in conjunction with a cap. The lower shelf height of this stud in comparison to the standard stud allows the product to accept the shorter eyelet length of the cap. Reversible studs can also be used with standard eyelets on thick applications as well as being used with screws to fix the stud on hard surfaces.
Screw Stud
A screw stud is a snap fastener stud that incorporates a screw in its design. Screw options available in most DOT® product lines include wood, self-tapping, self-drilling, and machine screw designs. Screw studs allow the use of snap fastener studs on hard surface applications where an eyelet cannot be employed.
Self-Piercing
Self-piercing is a term that describes the action of the cap and eyelet components of a snap fastener closure piercing their own hole as each is secured to its mating part through the attaching process. Self-piercing eliminates the need to punch a hole in the application material prior to making the attachment.
Snap Action
Snap action is the act of engaging and disengaging a socket and stud. The force required to complete either act is measured in pounds and the subsequent action is described as hard, normal, or easy based on the dimensions of the products.
Snap Combination
The two, three, or four components required to make a working snap fastener closure.
Snap Fastener
A snap fastener is a two, three, or four-part working closure of a socket and stud design that when affixed on an end item allows components of the end item to join or separate when required by the end user.
Socket
A socket is the component of the female segment of a snap combination that is designed to be resilient and accept the stud, thus completing the closure.
Stud
The stud is the male half of the snap combination and acts in conjunction with the socket to form a complete snap fastener closure.
Turn Button
A turn button is a specialty fastener that incorporates the function of a button and a stud. The fastener is assembled with a pin and spring attached to the button and stud, holding the button under tension until it is turned by hand.
Washer
A circular part of some snap fastener combinations that is used to secure other fastener components to an application. The different washer types accept the eyelet curl or prongs of their mating fastener thus completing an attachment.
Windshield Clip
A windshield clip is a metal spring clip with an attached stud. The dimensions of the clip allow it to be snapped onto standard sized windshield railings for boats and railings for truck tonneau covers.