The AAC 51 version shares the same distinctive and uncluttered shell as the rest of the About A Chair series.‎ The chair features a five-legged castor base equipped with a semi-automatic gas lift that can adjust the seat height from 42 to 56 cm.‎ The stylish, functional design combined with the elegant swivel base makes it perfect for formal or official settings and work-at-home offices.‎ The polypropylene shell is available in a large number of colour and upholstery options and the base comes in various finishes.‎ Injection moulded polypropylene shell without armrest with full upholstery.‎ 5 star swivel base in cast aluminium with wheels and gas lift.‎ With soft wheels for all floors.‎ Available in a large selection of standard fabrics and leathers.‎ Available in 3 different base finishes:- Black powder coated aluminium (RAL 9005)- White powder coated aluminium (RAL 9003)- Polished aluminium