STS SS4 Solid Source
STS SS4 Solid Source material may be used in similar ways to liquid source LS1, in that it can be spread in the training area on the ground, equipment, protective clothing, etc. without having any effect on these items. SS4 is a free flowing white powder which will not adhere to dry surfaces, so its use is limited to horizontal or near horizontal surfaces, in folds of cloth or clothing etc.