Neutronic Girdle has 7.5 Kinetic Resistance. Probably not a bug, per se, but if I'm not mistaken, it's the only decimal Resistance of any (player accessible?) item in the game.
As for the Neurotic Girdle, I've brought I up with the team, so it may or may not be changed. But for the time being, yes, a decimal value is a valid value to have for resistances, even if not many items are assigned that.
