We tested it during some hot weather, and found that its performance was good, mainly thanks to the numerous (28) vents on the outer shell. It could do with better internal channelling to really get the air flowing inside it though.
The retention system is one of its strong points. The wide cradle offers loads of support from its flexible wings. The turn wheel allows small increments of adjustment, which are ideal for getting the fit just right.
At the brow, the gel pads, also seen on the Bluegrass Goldeneye helmet, do a fantastic job of directing sweat away from the eyes. They are adequately comfortable too.
The Parabellum has a long visor, with a toothed angle adjust for simple adjustment. It could do with being a bit wider to offer better protection from sun and rain though.
The Parabellum's retention system and the adjustment it offers are high points