Super scarce Vintage Australian Pre-decimal "OS NSW' perforations 1 1/2d Green KGV Head Stamps + FREE Shipping 🛩 WITHIN AUSTRALIA ONLY. Combined shipping available. 'Renniks Stamps of Australia 17th Edition' CV =$110 for 1 'OS' perforations 1 1/2d green KGV Head stamp. Type 2(single crown over A) watermark, perforations: 14 . The 'NSW' perforations are even more scarce & this is 3 stamps vertically joined. 'OS' stands for 'Official Service' and were used by government departments as a safeguard against theft of government stamp stock, by its employees. It is assumed that mint examples exist because they were either substituted for with regular stamps, by reimbursement to the department with cash equivalent to the face value, or stolen. Beautiful condition. Photos form part of description. The stamps pictured are the stamps that you will receive.