The A3PB41-600R-11 is a 2-position momentary pushbutton from the PB series, fitted with a 44 mm red mushroom head and a 1NO+1NC contact block. The 44 mm mushroom actuator is the large-diameter style you see on E-stop or palm-actuated stations — sized for a gloved hand to hit it without fumbling. The momentary action means the contacts return to rest when you let go; it does not latch.
This part carries an EOL Hot lifecycle stage, meaning the manufacturer has formally ended production. No last-time-buy window remains open.