Check out Flowfit®.
www [dot] rmaxinternational.3dcartstores [dot] com/FlowFit_p_152.html
Yoga is not stretching. It is a balance of strength and surrender. It is about mobility, not flexibility.
Read the Prasara Yoga book for the theory on Yoga in modern physiology terms. www [dot] prasarayoga [dot] com
Check out Flowfit®.