Slow and steady wins the race. Blue #004 has a square frame with flat lenses. - Lens: Black (CR39) - Lens Category: 3 (100% UV) - Mazzucchelli acetate - Five-barrel (OBE) hinge These sunglasses is handcrafted with glossy brown tortoise Mazzucchelli acetate and brown CR-39 lenses with 100% UV (400) Protection. Equipped with OBE technology, the temple and front are connected by a five-barrel hinge. Complete with the engraved Chimi logo.