Works vehicle lane closed ahead (800 yards)

This sign means: Signs used on the back of slow-moving or stationary vehicles warning of a lane closed ahead by a works vehicle. It is a road works sign: slow down, follow the signs and keep to any temporary speed limit (Highway Code rule 288).

Official Highway Code caption: “Signs used on the back of slow-moving or stationary vehicles warning of a lane closed ahead by a works vehicle. There are no cones on the road.”

Listed under “Road works signs” in The Highway Code: traffic signs (GOV.UK). For every sign in more detail, see the Department for Transport’s Know your traffic signs.