Cheap pliers slip and round off your bolts. These never do.
Why Not Just Buy the Cheap One?
Cheap water pump pliers from Harbor Freight or Stanley have loose joints, blunt teeth, and a slip-prone grip that chews up nuts and pipes. Knipex uses hardened teeth that bite into metal, a push-button adjustment that works one-handed, and a box-joint design that stays tight forever.
The Buy-Once Math
A $10 pair of cheap pliers works okay for a while but starts slipping and rounding off fasteners, costing you broken parts and multiple trips to the store. Cobras cost $35 but last for life and actually do the job. You'll waste more time and money on stripped bolts than the pliers cost.