MSM 1000 mg Tablets (OptiMSM® U.S.A.-Made methylsulfonylmethane)

What the brand says

Features: OptiMSM is a proprietary form of U.S.A.-made methylsulfonylmethane. It is the purest form available and exceeds all customer specifications in this area.  Every batch is tested for water content, residual DMSO and also heavy metals which are important under California Prop 65 Every batch is made in an US-based single-purpose facility in Vancouver, WA. This eliminates the potential for cross-contamination and reduces the chance of impurities. OptiMSM is distilled for purity compared to other forms which use other less effective means to eliminate impurities (typically crystallization). Only OptiMSM has built the market for this material in the last 5 years. All of the important published safety and efficacy studies have been funded by Bergstrom Nutrition. Virtually all leading brand marketers in North America specify and use OptiMSM in their joint formulations.