This parasol base offers a sturdy and reliable foundation to ensure your umbrella remains stable and upright. Strong and stable base: This parasol base features a durable plastic shell filled with concrete, ensuring exceptional stability to keep your parasol securely in place and prevent it from tipping over, even in windy conditions. Easy movement: Equipped with lockable castors, this parasol base allows you to effortlessly relocate your parasol to any desired spot and securely lock it in place for added control and safety. Easy to install: This umbrella base has a tightening knob for securing your umbrella to the base more firmly. Compatible with multiple pole sizes: This umbrella base comes with 2 pole adaptors, allowing it to fit umbrella poles with a diameter of 38 and 48 mm.