Your own mask, fit is the most important thing if it isn't right, you're not having fun. Snorkel, it's going in my mouth only, not mine and the people who did the trip before me and rinsed in the same bucket as the 30 people who were on the boat with the person who had the snorkel in their mouth. Fins I don't mind using the ones on the boat, for the most part the saltwater keeps the athlete's foot at bay.