Commonly, products with sustained release (or timed-release) technology use "Thalates" (phthalates) to accomplish the slow release effect. Thalates are most often found in birth control, among other time release products. Thalates have gotten some bad press over the last several years because reports have linked them to negative side effects, like birth defects and cancer.
Jigsaw's w/SRT is completely phthalate-free, so there is no concern for thalate-related negative side effects from it.
Carnuba wax (which is the same wax used on cars) is another common mechanism used by companies to make a supplement sustained release. Jigsaw's s/SRT does not contain carnuba wax either.
Article ID: 461