If you're working with a monopod, you'll want the option of quickly attaching and removing you camera gear. Having a SIRUI MP-20 Quick Release Photo Platform that utilizes quick release plates (SIRUI has a wide range of QR plates to choose from) makes body/lens changes fast and easy. 

The SIRUI MP-20 Quick Release Photo Platform has a patented SIRUI-designed dual safety lock mechanism that prevents the camera from accidentally sliding off of the ball head (when the quick release clamp is slightly loosened). This feature is available with SIRUI TY-series Quick Release Plates (sold separately), and offers superior locking performance and reliability. 

Most Arca-compatible quick release plates can be used on the SIRUI MP-20 (Note: dual safety lock design is not available on other brands of quick release plates). 

And for precision alignment, the SIRUI MP-20 has a built-in bubble level. The SIRUI MP-20 Quick Release Platform can also be used on tripods!