"Designed to help improve your balance and flexibility, this yoga wheel set stretches your hips, abdomen, chest, and back in a safe way. Each wheel is made out of ABS plastic and TPE foam for durability, and they're also skin-safe and hypoallergenic."
"If you find yoga daunting because you're not flexible enough, a yoga wheel might help. This wheel by Ativafit was made to improve your balance and flexibility. This set includes three wheels for various levels of experience and a variety of stretches, and Ativafit says each piece is designed to assist you in building your balance ability, core, and back strength."