This is our top-of-the-line mouse guard. It is magnificent! This guard is crafted from a single, heavy-gauge piece of stainless steel. With quality like this, it's the last mouse guard you'll ever have to buy. Simply place our stainless steel mouse guard at the entrance of your hive before the cold weather sets in. The bees can get in and out through the holes, but the small entrances are too small for our little furry friends. Perforated entrance design also improves the hive's winter ventilation! You'll want one stainless steel mouse guard for each of your hives.