We needed to hit a 50cm diameter mirror-ball from 8.6m, suspended from the 6.5m high roof covering our Winter Wonderland scene below. The 4-degree beam seemed to be the best available option, and so once purchased, we checked the beam-size and were delighted to see a really bright beam of 57cm square when projected from the required distance, onto a red brick wall in full daylight. Fantastic. A well made, durable quality unit: compact, with an easy-to-fit/adjustable mounting bracket. Perfect for the job. Highly recommended.