Toothpaste – a local pun on its position at the end of Toothbrush Island – is the southern-end dive on Flinders Islet and a relaxed, shallow site that suits newer divers and makes a good second dive after the Bombo or a deeper island dive. The reef rises from about 24 m offshore to a flat top at 10–12 m, and the main feature is a two-to-three-metre wall of the distinctive pink rock seen all along the Wollongong coast.

The wall runs east from the usual anchor spot, turns north-east and then west to form a small point before swinging south again, so a slow circuit brings you back to the boat without much navigation. Between the wall and the extensive kelp beds is a corridor of boulders and rubble where most of the life is concentrated. The face of the wall and the boulders carry sea tulips, sponges and gorgonians in pink, red, orange and yellow. Large schools of bullseyes hang under the overhangs at the northern end, and big smooth and eagle rays – locally called bull rays – like to rest on the sand around the north-eastern point.

The kelp is worth exploring on a clear day for leatherjackets, wrasse and the occasional weedy sea dragon, and it is where you will find the most shelter from any current. There is nothing dramatic here in the way of caves or swim-throughs; the appeal is an easy, colourful, fish-rich dive with a simple route and depths that allow a long bottom time. Combine it with the cave and gutters at the northern end of the same island for a full morning's diving with a very short boat ride.

Launch from the Port Kembla boat ramp in the Outer Harbour (behind the steelworks; large car and trailer park, toilets). Wollongong Harbour's ramp (Belmore Basin) is closer to the northern islands but suits only small boats in calm seas. From Port Kembla steer out through the harbour entrance, keeping clear of the shipping channel, and head for the island; the run is 10–15 minutes in a small boat.

Run to the southern end of Flinders Islet (the 'toothbrush'). On approach the depth comes up from about 24 m to 15–17 m and then to 10–12 m where the wall starts; anchor here at 34° 27.512' S 150° 55.638' E. The flat reef gives poor holding in northerlies, so anchor deeper in those conditions.

The Five Islands sit in open water off Port Kembla and are exposed to all swell, but the islands themselves give lee on one side or the other: dive the northern ends in southerly swell and the southern ends in north-easterly conditions. Boats generally want less than about 1.5–2 m of swell and winds under 15 knots for the short run out of Port Kembla Outer Harbour; Wollongong Harbour's ramp is suitable only for small boats in calm seas. Visibility is often better than the inshore beaches, but drops after heavy rain when Lake Illawarra, Allans Creek and the harbour flush brown water out.

Best visibility is usually late autumn to early winter; winter westerlies produce flat seas. The southern end of Flinders Islet suits north to north-easterly conditions; a big southerly swell makes it surgy.

From the anchor follow the base of the wall east, staying in the gap between the wall and the kelp. Round the north-eastern point, where bull rays often rest, then continue as the wall turns west to form a point before heading back south past the boulder field to the anchor. The circuit takes about 20 minutes at a slow pace; spend the remaining time in the kelp if visibility is good.

United Divers (Fairy Meadow, Wollongong) runs boat dives to the Five Islands from Wollongong Harbour/Port Kembla when numbers and weather allow; Expedition Dive (Sydney) runs seasonal seal trips (June–Oct/Nov); otherwise private boats and clubs.