ซื้อTracheostomy silver No.2-6,Tracheostomy silver No.3-7,Tracheostomy silver No.4-8,Tracheostomy silver No.5-9,Tracheostomy silver No.6-10,Tracheostomy silver No.7-11,Tracheostomy silver No.8-12,Tracheostomy silver No.9-13,Tracheostomy silver No.10-14 โดยวิธีเฉพาะเจาะจง