40mm Ducted Fan Shroud

40mm fan ducted shroud for the prusa mendel with Lm8uu's and a J-head extruder. this has a flap inside that can adjust the amount of air to the hotend. It snaps in place between the LM8UU brackets but some additional doublesided tape or whatever might also be desired. the hotend duct lines up with the vents on the J-head mk4 extruder while the other duct shoots down evenly around the extruder (missing the nozzle) onto the freshly placed plastic. This is great for sagless bridging and sharper cor