Gabba innovation performance and comfort the gabba windstopper rain jersey is a textbook castelli product innovation the gabba is phenomenal because it keeps out the elements while offering excellent breathability and super stretch for a perfect fit when riding this version is light like a standard jersey but protects like a jacket it39s deceptively warm yet doesn39t overheat in moderate conditions and if you get rained on you get the bonus of gabba protection with this the latest