Dive Float & Flag
The float with a diver-down flag is the one piece of spearfishing gear that's about staying alive around boats - legally required in many waters, and the right place for your catch too.
Boat traffic is one of the most serious hazards a spearfisher faces, and the float with its diver-down flag is the defence: a buoy on the surface, tethered to you, flying the flag that tells every passing hull there's a diver below. Many jurisdictions require it by law and specify distances boats must keep. The float earns its tow in other ways too - it carries your catch (keeping struggling, bleeding fish away from your body in shark country), marks your position for your buddy and the shore, and gives you something to rest on between dives.
⚠️ Spearfishing is freediving - and freediving has real risks. Shallow-water blackout can strike experienced divers without warning: never dive alone (one diver up watching, one down - always), never hyperventilate before a dive, and get formal freediving training before pushing depth. Tow a float with a diver-down flag - it's legally required in many waters and it's what keeps boats off you. Load a speargun only in the water, never point it at anyone, and know your local rules: spearfishing is prohibited in fresh water and in many marine areas, and species, size and season limits apply. We describe gear and technique for education only - we don't give legal or medical advice; check your local regulations and train with qualified instructors.
What it is
A buoyant surface marker - inflatable or hard foam torpedo - flying a recognised diver-down flag, tethered to the diver (or the gun) by a float line, often with clips for fish and gear.
Where it shines
Everywhere, every time. There is no spearfishing situation - shore dive, boat dive, calm bay - where diving without a surface marker is the better idea.
How to use it
Rig the float line to your gun or a belt reel, keep enough line for the depth you're working (roughly 1.5-2× depth so the float doesn't drag you), clip fish to the float promptly, and rest on it between dives while you breathe up.
Choosing & sizing
Torpedo floats tow easily in current and chop; inflatables pack for travel; hard floats take reef abuse. Check your local flag standard (alpha flag vs red-and-white diver-down) and any required flag size.
Strengths & weaknesses
It can save your life, it's often the law, and it carries the catch - the only 'weakness' is drag in current, which better float shapes and line management mostly solve.
Common mistakes
Diving without one because 'it's just a quick dip', keeping bleeding fish on a belt stringer instead of the float, too little line for the depth (the float submarines), and a faded, illegible flag.