Features Stainless Steel Shell: Stainless steel oxidized black shell, high-grade appearance, good hand feeling, high-quality details, every part is made of precision, anti-drop and wear-resistant, non-fading. Self-locking: When you press the button, the key will speak into place until you press it again. Then press the button to return. High-quality Performance: IP65 waterproof grade, bright LED indicator, eye-catching light. Easy to Install: The mounting diameter is 19mm for easy installation and removal Wide Range of Applications: The switch push button is widely used in mechanical equipment, automation equipment, machine tool equipment, electric power, marine machinery, mining equipment, elevator control, medical equipment, access control systems, rail transit, industrial lighting, etc. Specification: Item Type: Push Button SwitchInstallation Diameter: 19mm Rated Voltage: 12-24VDC Emitting Color: Red, Green, Yellow, Blue, White(optional) Contact Structure: 1NO Shell Material: Stainless Steel Size: Approx. 27 x 19mm / 1.1 x 0.7in4 Pin: 1NO, positive and negative pole of power lamp, 1 common end Package List: 2 x Push Button Switch Package List 2 x Push Button Switch