This is the only MSM I am aware of:
Methylsulfonylmethane (MSM)

Scientific Name(s): Methylsulfonylmethane , DMSO2

Common Name(s): MSM

Uses
MSM is commonly used for osteoarthritis, but may also benefit in alleviating GI upset, musculoskeletal pain, and allergies; boosting the immune system; and fighting antimicrobial infection. Clinical trials are needed to verify these potential uses.

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Dosing
MSM commonly is given as 2 to 6 g/day in 2 to 3 divided doses for arthritis and other joint conditions.
Commonly used in the NFL
It is also a solvent.