The 601 series delivers 0.8 ml of foam per stroke — double the volume of a 0.4 ml pump, which suits hand soap, shower gel and foam sanitizer. The wide 40/410 and 43/410 collars sit on larger dispensers without an adapter, and the foam generator is tuned for higher-viscosity soap bases so the lather stays dense rather than watery. PP body, inner spring outside the liquid path, automatic functional test at AQL 0.6 before packing.