Mason Bee Inserts! It's vital to your mason bee's health to have clean holes each year

These refills are made of 100% recyclable paper that snugly fits inside the traditional guard tube.

• Compatible with other guard tubes and standard 5/16" hole blocks on the market.
• Easily pulled from either guard tubes with plastic stops on the back, or from Crown Bee traditional guard tubes with paper backs.
• If you are new to mason bees, please don't buy inserts only because they seem to be cheapest.  The walls are too thin to withstand pests and your mason bees will not live long.  Instead, either buy guard tubes to go with the insert, or try reeds or easytear straws.