How do Predators store their Combi-Stick?

Question

In the "Alien Vs Predator" series of movies, the Predators habitually carry a Combi-Stick on their backs.

Could somebody please tell me what keeps the Predators' Combi-Stick in place on their backs?

I'm aware that in the "AvP" toy the spear is held in place with a plastic clip but I'm fairly sure this is not what the Predators actually use!

Answer 1

There's actually quite a nice shot of the combi-spear in AVP1;

It appears to adhere to the Predator's armour magnetically, approximately halfway along its length.

Here it is from another angle. Again, there's no visible means of attachment which strongly suggests that it sticks on with magnets.