Motorway gantry sign
A gantry spanning the motorway with blue overhead signs indicating one lane exiting and two continuing ahead, and the following text.
Left lane destinations: M4 The WEST; Slough; Reading .
Right-hand two lanes destinations: London (W); Heathrow [Airport symbol]; (Terminals 1, 2 & 3) M4 .
Change Route: M4 The WEST or M4 London
The three-lane sliproad divides, a left turn to head west or a right turn to dive in to London.