INVINCBL GHD (Glute Hamstring Developer) is a performance optimization tool that is a requirement in all professional athletic facilities. The GHD is the only piece of equipment that stimulates and strengthens the posterior chain the way it does, that is why it was always a must have for professional athletes and is now gaining popularity with more commercial gyms. Made with high quality steel, padded with dense foam and fitted with a wide base, training your back, glutes and hamstrings has never been safer!