This Polaris twin 900 VES cylinder has the casting number 3021615 and is remanufactured with a lifetime warranty by the plating company.  We do require a core for this cylinder.  S/H is $16 anywhere in the Cont. US via UPS Ground, $46 to Canada via USPS Priority Mail International, or $60 to most other countries via USPS Priority Mail International.  and local pickup is welcome as well for no s/h cost. This cylinder has an additional core deposit of $150 which is waived if we receive your bad cylinder before sending this one. The easiest way to do this is to send payment along with the bad cylinder core.  Let me know if you have any questions. Thanks, -Paul (269) 838-0395