The Lembeh Straight is known for its excellent muck dive sites and Hairball is one of the best muck dive sites in the area. It is a typical black sanded dive site, so common in the area, with a few algae and sponges. It is visited primarily as a muck dive site as it has a large number of very well camouflaged marine creatures. They are very diverse and most divers visiting, say they spot something new on this dive site.
Hairball One is accessible all ear around with the best diving conditions being between July and October. This is the dry season and so the waters are calmer at this time. The dive site has a maximum depth of 30 metres but most divers find themselves exploring the sandy bottoms of the shallower parts from around 10 metres to around 5 metres. There is only ever a light current and visibility ranges from 5 metres to around 20 metres. The layout of the site is very similar to other dive sites, with gentle sloping black sand, some sunken logs, and other sunken vegetation. Hairball One is no exception and is made up of a large single slope.
The dive site is used both as a regular day dive but also as a night dive. Day time diving will allow divers to spot dragonets, devilfish, scorpion fish, waspfish, zebra crabs, cardinalfish, batfish, juvenile cuttlefish, many different types of frogfish, and many different brown and yellow seahorses. These sea horses seem to generally be unperturbed by divers and so can be seen moving around, a rare treat for any diver. Divers often spot octopus here as well; they use sunken coconut shells as a perfect temporary home. At night, there are a larger number of creatures to spot including cuttlefish, other types of frogfish, decorator crabs, and Spanish dancers. Divers often spot the cuttlefish eggs in their nests on this dive spot; these are a fantastic thing to find as divers can then see the juvenile unborn cuttlefish moving around in their tiny eggs.