What is not a requirement for leg-hold traps?

The correct choice identifies a feature that is not mandated for leg-hold traps. A digital tracking device is not a requirement for the use of leg-hold traps. While tracking devices can enhance monitoring and compliance with regulations, they are not legally required for the functionality or humane use of these traps.

In contrast, features such as shock-absorbing devices, trap pads, and double chain swivels serve important purposes. Shock-absorbing devices help reduce injury to trapped animals, making the trap more humane. Trap pads are utilized to increase the comfort of the animal being captured and can help minimize injury by distributing the pressure over a larger area. Double chain swivels allow for greater movement of the trapped animal, which can prevent excessive stress or injury. These requirements aim to enhance animal welfare and ensure that trapping practices align with ethical standards.