Silhoflex rib-less smooth back modern design with ergonomic shell that incorporates a built-in lumbar support. Shell passes CAL 133 testing with no additives. Frame made of 11ga. cold-rolled steel with exclusive Columbia 360⁰ brazed on foot extensions. Available with various glide options such as TPR, ARMOR, FELT and STEEL that makes the chair suitable for any surface. Available in a variety of heights.