... used or together with other bases 2,Easy to stack,better wind resistance 3,Unbelievable low cost ... ,lower cost,high performance-price ratio4,Easy to stack,sure to reduce your shipping cost PRODUCT DETAILS PRODUCT SIZE:Individually ... MATERIALMade by HDPE,UV resistant. Features1)Perfectly stacked to keep the base stable in the wind2)Much lower ... design water tank for flying banner/easy to be stacked