These are Nice and very popular Black Mesh Back Office Swivel Desk Chairs with a free Tilt option and a pull away Arms as pictures show. price is for each chair 4 Available 
The chairs are a nice large size .seat width between the arms is 52cms and seat depth to backrest is 47cms. max seat height is 51cms
very comfortable Chair with its Perforated Foam cushion padded sest
please look at my other commercial items