The base is designed for this bread box from Amazon. 

It's meant to 

• prevent the bread box from shifting
• lift it off the countertop so any water spilled doesn't absord into the wood and 
• add some storage spaces on the side. 

There are recessed slots on the bottom for 3m double sided tape so it sits close to flush

Square Oil Bottle Slot is 60mm x 60mm

Circular Spray Oil Slot is 70mm diameter

Rectangular Cookbook Slot is 55mm x 235mm

The trays fit underneath with a bracket to stop them from being pushed too far back