The nozzle provides adequate pressure to force water under debris that has adhered to the base of the gutters and can push that debris towards your drainage spouts.
Reaching your gutters from the ground.
Using pvc pipe and fittings for less then 10 you can clean your rain gutters fast and from the ground.
To clean high gutters with a ladder you ll need to ensure the ladder is stable and then methodically clear the gutter by hand.
To clean gutters from the safety of the ground make a homemade gutter vacuum using a wet dry vacuum then pass the gutter vacuum over the gutter to remove debris.