The IDEC HW1B-A4F01-Y is a robust 40mm mushroom push button designed for maintained operations. It features a single normally closed (NC) contact and a yellow plastic bezel for high visibility. The unit's finger-safe IP20 contacts and tamperproof construction ensure user safety and device integrity. This emergency stop push button complies with EN60947-5-5 and SEMI S2 standards, making it suitable for critical applications where reliable performance is essential.