What kind of mechanical-type timer provides a single fixed-timed output for a set period of time?

The correct choice is the interval timer. An interval timer is specifically designed to provide a single output for a predetermined duration, activating for that set period before automatically turning off. This makes it ideal for applications where a task needs a precise timing sequence, such as turning something on for a specific length of time and then off.

On-delay timers, in contrast, activate after a specified delay once an input condition is met, which can lead to a situation where the output is held for an indefinite time based on the condition remaining true. Off-delay timers operate differently by keeping the output active for a set duration after the input condition is removed. Recycle timers can repeat the on-and-off cycles continuously, based on the preset time intervals.

Understanding how an interval timer functions is crucial for tasks that need a singular, fixed operational time without the need for repeated cycles or dependency on continuous input conditions.