The Schneider Electric Telemecanique Harmony XB4BA21 is a 22 mm black flush non-illuminated momentary pushbutton with spring return and a single normally open contact for panel-mounted operator control. It features screw clamp terminals, a chromium-plated bezel, and a Zamak fixing collar, with dimensions 47 × 30 × 52 mm and IP66/IP67/IP69/IP69K protection, operating from -40 °C to +70 °C. Rated for 10,000,000 mechanical cycles, it supports start, cycle initiation, reset, or jog functions in industrial control panels, machinery, conveyors, packaging equipment, and other automation applications.
