What shotgun action requires you to slide the forend back and forth?

The shotgun action that requires you to slide the forend back and forth is the pump-action shotgun. In this design, the shooter manually operates the forend to eject the spent shell and chamber a new round. This action allows for quick follow-up shots but requires the user to actively engage with the forend for each shot. Common examples include the Remington 870 and Mossberg 500.