1.PP fixed armrest. 2.Gas lift,the seat can be adjusted in height. 3.PP base 4.PP Caster 5.This is Ergonomic design. 1,Product pictures 2,details 3,packing 4,certification 5,contact us Welcome to visit our website and factory. QQ:1051869997 Mob: +86 18317552143Tel: +86 379 62277510Fax: +86 379 62277510 We are ready to join hands with you!