they're either 15.5 or 16.2mm Oetiker style crimp clamps. if you go to an autoparts store (read: not fucking autozone) and ask for fuel injection hose clamps they work really well and don't screw up lines like the slotted worm screw ones. if you do get a worm clamp make sure they are an inverted non slotted style pretty sure the 5/16" ones work really well on the thick lines. this is a huge constant tension style like you would want to use on a boost hose on an intercooler. this is just a good pic to show you what you want, not the ghetto slotted ones with holes.
