Because most eyeglass frames don't come with a clip. Your customers have to buy another frame and lenses for sunglasses. Many don't. Or won't. Eclips offer a wide variety of lens options, extending the selection you can offer your customers. Eclips means lower inventory costs... No more getting stuck with discontinued clips. Eclips chassis are universal by design. Eclips are reusable... The hardware is good forever. If the lenses are scratched, replace them. Eclips can be made in your lab or ours. Eclips are simplicity itself... Lenses & Chassis. (a top bar and four fittings with adjustable prongs) That's it! No other custom clip fits as well as Eclips.