Carriers are obliged to provide Instructions In Writing in the cab of every transport unit they operate in a language the vehicle crew can understand. The IIW (Instructions in Writing) detail all vehicle kit and PPE needs per hazard class. The most recent version can be downloaded free from the UNECE website or they are commonly available in laminated format. The requirements for vehicle kit may vary according to products carried. The following list is a comprehensive breakdown for a Packages vehicle carrying hazard classes 2,3,4,5,6,8 and 9: