Sahih al-Bukhari

Narrated `Abdullah:

Regarding the Verses: 'And was at a distance of but two bow-lengths or (even) nearer; So did (Allah) convey the Inspiration to His slave (Gabriel) and then he Gabriel) conveyed (that to Muhammad...' (53.9-10) Ibn Mas`ud narrated to us that the Prophet (ﷺ) had seen Gabriel with six hundred wings.