GW OTS Single Quartz Heaters are used when the corrosion resistance of the quartz glass tube is desirable. Grounded metal heating element are insert into the quartz glass which are designed to allow replacement of elements within the tube. All GW’s quartz heaters are supplied with “One-Time” thermal fuse preventer as over-heating. Special design liquid tight terminal cover prevents entry of liquids. Due to the nature of quartz (glass), polypropylene (PP) protection guards are recommended.