This document is an instruction manual for HI 93751 Sulfate ISM instrument, which describes the design, construction and appearance of the instrument. The instrument is warranted for two years against defects in workmanship and materials when used for its intended purpose and maintained according to instructions. Damages due to accident, misuse, tampering or lack of prescribed maintenance are not covered. If service is required, contact the dealer from whom you purchased the instrument. If under warranty, report the model number, date of purchase, serial number and the nature of the failure. If the repair is not covered by the warranty, you will be notified of the charges incurred. To validate your warranty, fill out and return the enclosed warranty card within 14 days from the date of purchase. All rights are reserved. Reproduction in whole or in part is prohibited without the written consent of the copyright owner, Hanna Instruments Inc., Woonsocket, Rhode Island, 02895 , USA.