The Garmin T-5 collar works with the Astro 320, Astro 430 or the Alpha 100. This collar comes with improved top-mounted GPS and GLONASS receiver/tracking, rechargeable/replaceable 20-40 hour Lithium-ion battery, sitting/pointing/moving/treeing indicator, 9 mile range, water-proof to 10 m, rescue mode, LED Beacon lights for low-light conditions, and a 4-digit Collar Lock to prevent others from tracking your dog. When purchased as an add-a-collar, this collar comes with a blue strap.
The T5 mini provides all the features as the T5 in a smaller case (about the size of a shock collar). It uses a 3/4″ strap, freeing up room on your dogs neck, and advertises a 4 mile range with a battery life of 16-30 hours.