A post hole digger is a manually operated tool designed to make the difficult and exhausting task of digging holes easier.
It works by being thrust into the earth, with the blades in an open position, until they pierce the ground and are buried beneath the surface. When repeated a few times, this motion starts to loosen the soil, allowing the blades to go deeper into the ground with each thrust.
The handles are then manoeuvred in to close the tool, bringing the blades together around the loosened soil.
The blades clamp the soil within so that it can be removed from the hole by lifting the whole tool upwards.
The process is repeated until the hole is deep enough for the post to be fitted.