Shoes are mainly used to complete an installation where a plain downpipe was installed and needs a shoe to direct the water flow away from the foundation.
Holderbats are used to hold the downpipe firmly against the wall to ensure a neat finish. At least two holderbats should be used per standard 2.7m length downpipe. It is not recommended to use less than two holderbats
The main purpose of an downpipe connector is to enable the installer to do an installation where it is required that the downpipe must continue more than one length.
Pipe clip is a holder bat to fix your downpipe against the wall. The benefit is that you can remove the down without the need of any tool to paint the wall.