Castelli Emergency 2 Rain Jacket As the name suggests, the Castelli Emergency 2 Rain Jacket is designed for use in sudden downpours. Completely waterproof Deluge Light 2.5-layer fabric is paired with a waterproof zip and contrast seams, creating a complete barrier. The garment is small too, packing down into its own stuff pocket and easily into a jersey pocket. A mesh vent at the top of the back keeps the air flowing to prevent overheating and the Emergency 2 is finished with 360? reflectivity for added safety in poor conditions and after dark.