As-Salam by a definite known specified measure Sahih al-Bukhari 2239b

Arabic hadith text
حَدَّثَنَا مُحَمَّدٌ، أَخْبَرَنَا إِسْمَاعِيلُ، عَنِ ابْنِ أَبِي نَجِيحٍ، بِهَذَا ‏"‏ فِي كَيْلٍ مَعْلُومٍ وَوَزْنٍ مَعْلُومٍ ‏"‏‏.‏
Translation
Narrated Ibn Abi Najih

as above, mentioning only specific measure.