The 4536RTSS Locking Retractable Stainless Steel Bollard retracts fully below ground, sitting flush to prevent any obstruction and tripping hazards. This retractable bollard can be locked in an extended, upright position for advanced perimeter security, and in its lowered position for quick access to restricted areas. A single key-locking mechanism contributes to the efficient, user-friendly design of this bollard. The clean and versatile design is highly visible and available with alternative mountings for consistent aesthetics that suit any modern building or landscape. High-quality 316 grade stainless steel with a satin finish features high resistance to corrosion and weathering.