ISO 20383:2017规定了速度识别标志（SIS）的尺寸、特征和位置。这些标志表示基于农用车辆的地面速度设计能力的最大设备地面速度。 在从后面接近设备的公共道路上，其他操作员可以看到后向SIS。安装在被牵引设备前部的前向SIS向牵引车操作员发出警告，告知设备组合可操作的最大指定地面速度能力。 ISO 20383:2017适用于在公共道路上移动的自行式、半整体式和牵引式设备。

ISO 20383:2017 specifies the dimensions, characteristics, and positioning of Speed Identification Signs (SIS). These signs indicate the maximum equipment ground speed, based on the ground speed design capability, for an agricultural vehicle. A rear-facing SIS is visible to other operators on public roads approaching the equipment from behind. A forward-facing SIS, mounted on the front of towed equipment, alerts operators of the towing vehicle of the maximum specified ground speed capabilities at which the equipment combination can be operated. ISO 20383:2017 is applicable to self-propelled, semi-integral and towed equipment moving on public roads.