Killark GZB3-B4 - Operators are all aluminum except for certain movable parts which are stainless steel. All other parts such as screws are either stainless steel or plated steel. Threaded bodies are all 3/4”-14 NPSM thread and M22x1.5 on request. Control operators can be grouped into a single assembly thus reducing installation time and cost. Killark GZ SERIES Operators are a component for use in conjunction with a Hazardous Location enclosure to provide control solutions for; START/STOP Motor Functions, LED Pilot Light Indications and more. Utilized in Class 1 Division 1 & 2, Class 1 Zone 1 & 2 areas for indoor and outdoor use. UL Listed and CSA Certified. ATEX/IECEx certified components. See Product Details for certificate numbers.