This set includes the components for your heated bed at a discounted price. You only need a carriage to mount it on, preferrably something with a flat surface (MDF) to keep the heated bed straight. Also some bulldog clips or kapton tape to keep the glass in place might be useful.
ReprapWorld is the number one webshop for all your reprap supplies for your 3D printer. We have a large collection of 3D printer components, from our famous electronics lines to filament from our own production. And everything is at a very competitive price!