Duratech 4″ × 5″ Survey Marking Flags – 24″ Plastic Staff – Yellow (Case of 1000) Duratech 4″ × 5″ survey marking flags with 24″ plastic staff provide a durable and highly visible solution for marking utilities, survey points, construction layout, and site boundaries. Manufactured from weather‑resistant 4‑mil vinyl and mounted on a 24″ PVC plastic flag staff , these flags insert easily into soil, gravel, or turf and remain noticeable in demanding jobsite conditions. Flags are sold per case of 1000 (20 bundles of 50), making them ideal for survey crews, utility locators, and construction professionals requiring dependable marking supplies in bulk. Yellow flags follow APWA / One‑Call utility marking standards and are used to identify gas, oil, steam, petroleum, or gaseous materials , including natural gas distribution lines. Key Features • 4″ × 5″ vinyl flag size – industry standard for utility locating and construction layout • 24″ PVC plastic staff for easy insertion and visibility above grass or soil • Durable 4‑mil vinyl construction resists tearing, fading, and weather exposure • Weather‑resistant design built for outdoor surveying, construction, and utility locating work • Sold per case of 1000 flags for convenient bulk purchasing and large‑scale projects