Oiselle Size Chart The Go Tank has more "go" than a marathon maniac with bionic knees and an I-V of Seattle coffee. It can't be stopped. Which is why it returns again and again, ready to tackle any hot run or sweaty spin bike. Features: - Highly breathable, lightweight athletic mesh - Easy layering piece - 20.5" body length (size 4) - 87% poly / 13% elastane