Winstrol is a really interesting variant of Dihydrotestosterone. It's been modified at the A-ring (there's 4 rings on steroids usually), to make another whole "ring" called a pyrazol group. There's only one other steroid I've ever seen that has a similar modification. Winstrol is a commonly used anabolic steroid for cutting cycles, and certainly it's been shown clinically to not elicit any really impressive weight gain (if any at all). It's usually seen as a less expensive alternative to Anavar. And just like Anavar and other DHT derivations, it can not convert to estrogen at any dose, and is not progestenic.  British Dragon Gear produces our brand of Winstrol called Winstroll™.