This is a hand made product. The glass tubes inside the frame act as natural holes. But you will be able to see the bees nesting inside the glass tubes. Most of these bee homes are made from repurposed wood materials. So, somtimes each home might vary from one another.
 
HOW SOLITARY BEES NEST: The female deposits eggs in the tubular holes in the wood. The bee will seal each egg typically with mud and saliva to form a waterproof cacoon with layers of pollen loaf for after the egg hatches into a larva to eat as food. The larva will contiue to eat unitl spring and begin to pupate and form into a a full grown bee. Male bees typically emarge first to wait for the females so they can mate and fertilize the females so the cycle can start again.