National Public Seating NPS 200 Series Premium All Steel Double Hinge Folding Chair, Red, Pack of 4 Sound Level dB85 Sound Level dB85 Recommended Applications Breakroom & Hospitality Product Type Chairs Stools Folding & Nesting Chairs Seat Color Charcoal Back Color Charcoal Color Family Gray Arms Included No Back Height Adjustment No Pneumatic Seat Height Adjustment No Seat Glide Mechanism No Tilt Tension tilt Lock No Knee Tilt No Synchronized Knee Tilt No Dual action Tilt No Posture Lock No Multi task Control No Asynchronous Control No Dual clutch Posture Control No Variable Synchro tilt No Integral Lumbar Support No Overall Width Maximum 18 National Public Seating NPS 200 Series Premium All Steel Double Hinge Folding Chair Two double riveted U braces one in front and one in back securely support the double hinged legs