This Larsen Trap is a traditional device for the humane trapping of magpies or other types of crow*. To attract magpies, a call-bird (or decoy) is placed inside the cage's largest compartment to act as a lure, and when the intruder enters the door on the top of the cage and lands on the perch below, it triggers the trap, safely catching it. It is very important to ensure that the decoy bird is well fed and watered, provided with shelter and checked at least once a day.*NB: In the UK it is illegal to use a Larsen Trap to catch other bird species. Galvanized to resist rust. Carry-handles on the top of the cage. Supplied flat-packed. Requires assembly - full instructions included. Strong and durable construction.