With 1 small and 2 large dice concrete cubes there is already a lot to build.
a furniture for your entry hall big enough to store your board or even your Brompton (yes, it fits!), an asymetrial stand, some storage under your stairs...
What will you build today?
colorless water and oil repellent matt varnish
Outdoor covered use
For outdoor use under cover, protected from rain and sunlight. Off-season, cover them with a 100% waterproof polyester cover: waterproof, UV resistant and air permeable.