The vowels of RP MOUTH

The RP diphthong begins near the front open position, lips spread: some retraction is to be expected, although this is not considerable. The glide then proceeds towards, though not completely to, FOOT. Trad-RP sees a startpoint that is centralized rather than only retracted, and may encompass  as well as . (The most retracted forms, accompanied by lengthening of the first element of the diphthong, are typical of Refined RP.)