Attributes . - 5 x Caster - 1 x Base - 1 x Seat Post - 1 x Seat Post Cover - 1 x Backrest - 1 x Backrest Post - 1 x Backrest Screw 8x10mm - 2 x Armrest - 2 x Arm Width Adjustment Knob + Washers - 2 x Arm Bracket - 1 x Mechanism - 3 x Mechanism Bracket Screw 8x20mm + Washer - 1 x Seat - 1 x Backrest Post Bellow - 2 x Backrest Post Bellow Screw 4x16mm - 1 x M5 Size Allen Wrench . Names