Product Name: The Back Stretcher is designed to help alleviate back pain, improve posture, and promote overall spinal health. Material: Made from high quality EPP material, this back stretcher is durable and sturdy, ensuring long lasting use. Lightweight: This back stretcher is lightweight and portable. You can easily carry it to your yoga class or anywhere you want for a quick stretch. Adjustable: Adjustable 4 step tensile strength. The surface and bottom groove design of the base can be easily stacked. 4 height levels can be freely combined to increase or decrease tensile strength. Wide ApplicationsThe Back Stretching is widely suitable for home, gym, exercise, yoga, Pilates, fitness, workout, etc. Specification: Material: EPP Size Chart: 20cmx25.9cm/7.87inchx10.20inch Package Includes: 1 SetBack Stretcher Note: Please allow slightly errors due to manual measurement and different monitors.