Oakley HSTN RX OX8139 813902 is a modern round prescription frame that combines lightweight construction with a distinctive trigger-stem design for everyday wear. Key attributes: Gray | Transparent | Nylon | Lightweight construction | Durable frame | Compatible with prescription lenses | Trigger-stem temple for secure seating | Modern round lens shape | Full-rim frame | Trigger stem design | Dimensions & fit: Lens width: 50 mm | Bridge: 21 mm | Temple length: 140 mm | Frame height: 46 mm | Regular fit | High bridge fit | Composition & care: Nylon | Clean lenses with a microfiber cloth. Wipe frame with a damp cloth and mild soap. Avoid solvents and excessive heat.