Elastic Ring ( Aclathan ring ) as per RDSO [ Elastic Ring ( Aclathan ring ) as per RDSO specn. No. RDSO/ 2007/ EL/ Spec/ 0053 Rev- 2, and as per RDSO Drg. No. SKEL- 4717 Alt- 4. Note: Offers from RDSO approved sources or supplier of above item offers only shall be considered with valid tender specific authorisation certificate from RDSO source shall be submitted along with their offer. Otherwise such offers are liable for rejection. ]