Queen excluder cage Single frame

When July arrives and colonies roar with activity, it’s time to act with precision. Another treatment won’t fix the problem—you must interrupt the brood cycle at the right moment, before winter bees are produced but while nectar is still coming in. In most of the northern hemisphere, this means July–August. In September it’s too late. That’s where this one-frame metal queen isolator becomes a powerful biotechnical tool against varroa.

European build and professional design

Made in Europe from high-durability galvanised steel, this isolator is precise, robust and long-lasting. Its 4.3 mm excluder grid allows workers to pass freely while blocking the queen and drones. The removable metal lid lets you introduce or release the queen without opening the hive or damaging the frame.

The biotechnical principle that really works

The method relies on a brood interruption of at least 24 days, extendable to 28 if drone brood was present. During this period all sealed brood emerges, forcing varroa into a full phoretic stage on adult bees. This is the ideal moment to apply oxalic or formic acid with maximum efficiency. After release, the queen resumes laying strongly and the colony restarts with minimal mite pressure.

Scientifically validated technique

Based on the approach described in “Summer brood interruption for vital colonies”, this method is now standard among technical and organic beekeepers as a sustainable alternative to routine chemical treatments.

Useful applications throughout the year

• Comb renewal: isolate the queen on new wax to empty old combs fast.
• Nuc creation: improves queen acceptance in small colonies.
• Queen capture and marking: very practical for splits or queenless hives.
• Selecting breeder queens: evaluate laying patterns without interference.
• Transporting queens: far safer and better ventilated than plastic cages.

Usage recommendations

• Day 0: introduce the queen on a clean or freshly laid frame.
• Days 1–24: check every 5–7 days; ensure food reserves are stable.
• Days 24–26: optimum window for oxalic/formic treatment.
• Days 24–28: release the queen to align brood restart with winter-bee production.

Realistic limitations

• Requires strong colonies.
• Needs regular checks and proper timing.
• Remove drone brood or extend to 28 days.
• Use new or freshly drawn comb to avoid refusal to lay.
• Excellent moment to replace an old queen.

Who is it for?

Professional beekeepers, organic operations and anyone managing enough colonies to justify structured varroa control.

Advantages over other systems

• Plastic deforms and propolises.
• Wood cracks.
• Larger isolators are heavier and slower to handle.
This one-frame European metal isolator is clean, durable and extremely reliable.

Technical specifications

• Type: one-frame metal isolator
• Galvanised steel
• 4.3 mm grid
• Removable metal lid
• Fits Layens, Langstroth and Dadant
• 600–800 g
• Service life > 15 years

Maintenance

Hot water + 5% caustic soda, rinse, sun-dry; flame-sterilise if disease is suspected.

A precise European tool for beekeepers who want scientific, effective varroa control without complicating hive work.