VISOCOLOR® HE test kits are highly sensitive colorimetric test kits. In comparison with conventional VISOCOLOR® kits, their sensitivity is enhanced by increasing the length of the test tube and the use of highly sensitive reagents. This technique allows a 10-fold to 100-fold increase of sensitivity. Each VISOCOLOR® HE test kit is packed in a sturdy plastic box which contains the comparator block with colour comparison disk and all required reagents. The VISOCOLOR® titration test kits are based on principles of volumetric analysis. On the gradated syring the results can be read off in mg/l or in a second alternative dimension.