A solid understructure is the foundation of any telescopic system, and Irwin Seating leads the way in overall performance with the Model 4500 system. This telescopic understructure is designed for heavy-use facilities and has been used successfully in many major university and arena venues. The system is highlighted by its outstanding support roller system located at the deck support and cantilever locations. This and the many other details shown below ensure safe, smooth, and consistent operation. For more information contact your Irwin Seating representative.