* Make sure the powerhead you order is of the correct diamater for the spear you're going to use it with. We will not exchange a powerhead for one of a different size or replace it with another product because there is no way to inspect whether the inside seal has been compromised by the user.

This power head is designed to be used as shark defense. It is a quick slip on single use powerhead made of aluminum. It holds a sealed in 7.62 X 39 Remington 145 grain round (AK-47 round). This powerhead is spear actuated, there is no moving firing pin and as such it is legal to carry on one's person or in the car. The powerhead is deployed when the tip of the spear strikes the primer through a water tight seal on impact with the shark. The spear hole is machined with very little tolerance and as such does not allow play when the shaft is fired from the speargun. Common misfiring which is due to the spear point striking off the primer is non existent. Comes in different diameters to fit 6.5mm, 9/32(7mm), 7.5mm or 5/16(8mm) shafts. Our neoprene belt pouch holds two powerheads.

Features:

• Powerful round is enough to kill a shark depending on shot placement or at minimum severely wound it to the point of discouraging it from returning.

• Very quick to mount on spear, especially if used with belt pouch

• Sharp edge all around the front end helps it catch on the shark on angled shots.

• Built in O ring for snug fit. The powerhead seats tightly enough on spear that if target is missed the powerhead will not come off due to inertia when the spear is stopped short by the shooting line.

• Machined grooves provide grip when mounting on spear with bulky gloves.

• Water escape hole for easy insertion of the spear.

• Completely waterproof, the round is sealed inside on both ends and as such requires no maintenance.
• The powerheads are coated with a clear coating. This keep them looking new longer, aluminum will normally look dull grey in color after exposure to salt water.

We know from personal experience and have received feedback from other divers, that the common reloadable powerheads which use the little piece of rubber hose to retain the round and fit the powerhead over the spear, consistently fail to deploy. This happens because the spear point strikes away from the primer. Water resistance/drag act on the powerhead as the shaft is fired moving it enough to displace the spear point, the rubber hose piece can't keep the spear point in position. This is easy to see upon inspection of the round that misfired. There will be a dent outside the firing area.

A machined aluminum PH with very close tolerance to the diameter of the shaft does not allow this to happen. The spear point strikes in the same spot every time. For this design to work the round must be inserted from the front. In this case there is no other way to keep it in place except with epoxy, and in turn doesn't allow reloading. We suggest to those of you who own a reloadable powerhead to test it before you need it. While there is a comfort element in presuming you are protected, we believe it's better to know for sure rather than be under a false assumption.

About reliable reloadable powerheads

Beco make a reliable reloadable powerhead. The question is why is such a powerhead not suitable for freedive spearfishg as shark protection? These are the reasons:

1. It takes too long to put on the spear, secure in place and remove one or more safeties in a tense situation.
2. For consistent effect on a shark a powerful round is required. To accomodate this size round the stainless steel powerhead would have to be too big and heavy to allow reasonable range when mounted on a speargun shaft. So the powerhead is made to use smaller caliber rounds which are less effective.
3. It can be deployed by accident, such as by being dropped on the floor or deck of a boat.
4. The legality of moving one around on land may be questioned.

A compact single use aluminum powerhead solves the problem of weight and range while allowing for a powerful cartridge. At the same time eliminating all risk of accidental discharge and any legality issues. If the aluminum powerhead were to be manufactured to allow reloading, cost would increase while the probability of rendering it useless after discharging will stay the same, not a good deal. This combination of factors makes the Speardiver single use powerhead the best solution for freediving spearfishermen.