The Westinghouse foam cannon is well constructed with brass and steel parts. The 34 ounce solution bottle is strong plastic without flexibility (a good thing). Turn the mixing knob on top fully clockwise to draw the soap solution out maximally; turn it counterclockwise to spray water. I didn't feel that there was much granular mixing between full closed and full open, but I wasn't looking for that, so all good. My electric pressure washer has 1700 psi and 1.3 gpm which was fully adequate.