HealthSpan Plus Labs Ergothioneine 5mg, 60 Capsules

What the brand says

Ergothioneine- a food-derived amino acid (found in certain mushrooms in high concentrations) that is thought to play a crucial role in supporting long-term health through its cell-protective benefits and inhibition of free radicals. One daily capsule provides as much L-ergothioneine as 2 to 5 cups of white button mushrooms. A recent mouse study showed an amazing 21% lifespan increase.