Similar to Air Grid, but offering a look and feel all its own, The Matrex fabric used on the backs of these chairs is incredibly tough and resilient. The 2300 and 25004 feature adjustable lumbar support and an innovative 2-to-1 mid-pivot mechanism that puts the center of gravity towards the front of the chair to give you a wider range of motion while keeping your feet firmly on the floor. All three models come with a rugged mesh seat and soft padded armrests atop sloping, adjustable arms.