I'll also state I have no affiliation with the product or the manufacturer.
I'm rather partial to flathead fillets and as such flatties tend to be the only fish I keep.
They are kept in happily in my live well while on the water, and once back at the launch, they are "brain spiked" with my fillet knife, filleted, skinned and packed into ice sheets in my esky.
Not too long ago, my trusty fillet knife was mutilated by an inferior sharpening product and I had to replace it.
The knife I replaced it with is a little longer and more flexible. This created a problem when trying to brain spike flatties. The knife was too flexible to do the job properly.
Before I reverted to a sharpened screw driver I had a look around the internet to see what else was available.
I came across the "Ikigun". Although I thought it a little gimmicky, I'm never one to shy away from a gadget, so I bit the bullet and invested in one.
Its basically a gun that you retract a blunt spike by pulling a handle, which is released with quite a bit of force when you pull the trigger.
From Ikigun Website: http://www.ikigun.com/
The first thing that stood out to me when picking up the gun was the weight. It looks like a toy but is a solid bit of gear and well put together.The Ikigun is the latest innovation in recreational fishing enabling fishermen to rapidly & humanely kill their fish using the 'Iki' method.
It is a powerful piece of equipment made from materials selected to withstand the harsh marine environment.
I would not let your kids play with it, and the power of the thing has me almost questioning it's legality.
You could do some real damage with this thing, and I would be very careful with it if using on your yak while on the water.
Underneath the main spike is a small "Aiming Spike". I thought this was a little unnecessary but in practice, it works quite well and the gun is better for having it.
It helps hold the fish still. The retractor handle has a hook on the end, which makes it possible to load the gun on the edge of a cleaning table while you have the fish in the other hand.
How does it perform?
Well, I have never seen a fish go from lively to stone cold dead so quickly.
I am totally sold on this thing. The blunt spike has no trouble what so ever penetrating a flathead skull, pulverising the brain in a split second.
While the gun is bloody awesome, a knowledge of fish anatomy is a must for this tool to be effective.
This can be all found here: http://www.ikijime.com/
There are also smartphone apps for quick reference.
Summing up, while its not something everyone would be prepared to fork out for, it is a quality bit of gear that does exactly what it claims to do.