Eureka!’s new X4 structure is designed to meet the demand for engineered product in 30– and 40–foot core sizes. Lightweight and easy to install, the structure is engineered to 50mph. The 30– and 40–foot sizes have interchangeable parts in each 15–foot bay and there are no tools or bolts required for installation. TheÂ X4 takes only one pin throughout the entire system, and the standard pin size can be replaced with nuts and bolts found at any hardware store. Available with 8– or 10–foot legs.