This foamer is suitable for people experiencing frequent clogs due coil scale from a hot water power washer or debris/minerals in the water. The Clog Free version has a nylon mesh agitator screen instead of a stainless mesh pad. The nylon mesh can be rinsed and is less likely to clog.
For use with hot water machines it is recommended to swap out the agitator pad periodically. Most issues with a foamer are related to the agitator pad getting clogged with coil scale or debris in the water.
You can find Replacement Agitator Pads here.