Inquiry (采购产品): Model 00410 I need information on S/N H-00604 made in 1976. It has a canister type filter. How often does it need changed, what type of monitoring system does it require, etc? **** Hidden Message ***** Linda Warner 47601 Company: Mohler Technology Inc. E-mail: linda.warner@mohler.com **** Hidden Message ***** linda.warner@mohler.com
