Saint Laurent SL M131 Sunglasses pair the brand’s flat‑top square silhouette with an acetate frame for a refined everyday style. The design accepts prescription lenses and adds a subtle YSL monogram on the hinge for a signature finish. Key attributes: Black | Acetate | Prescription lens compatible | Flat-top square frame | YSL monogram logo on hinge | Squared silhouette | Dimensions & fit: 52/20/140 | Medium size (52 mm lens, 20 mm bridge, 140 mm temple) | Composition & care: Acetate frame | Nylon lenses | Wipe lenses and frame with a soft, lint‑free cloth. Store in protective case when not in use. Avoid exposure to extreme heat or chemicals.