Front element for push button Harmony ZB4F. Lens blue, text unlabeled. Design flat, with detent, without indicator light. Mounting diameter 30.5 mm. With high vibration resistance and chemical resistance, ambient temperature -40 to +70 degrees C. Chrome-plated metal, 1,000,000 cycles. Certifications UL listed, CSA. Product standards CSA C22.2 No 14, EN/IEC 60947-5-1, EN/IEC 60947-5-4, UL 508, EN/IEC 60947-1, JIS C 4520. Protection class up to IP69K.