Whirlygig Riser Forms

Whirlygig’s groundbreaking one-piece thermoplastic Riser Form revolutionizes manhole installation. Engineered to resist corrosive environments, it is lightweight—roughly 1 pound per inch of height—providing enhanced safety by reducing strain on installers' hands and backs. Paired with the Radial Arm Trimmer (RAT), it seamlessly adjusts for variations between the manhole cone and the road surface, enabling faster, more cost-effective, and higher-quality installations compared to traditional techniques.