Codex Alexandrinus is one of the four Great uncial codices and among the earliest and most complete manuscripts of the Bible. It is the oldest manuscript to use larger letters to indicate new sections, and it was the first manuscript of great importance and antiquity to be extensively used by textual critics.

It is a palimpsest where the original 5th-century biblical text was washed off and overwritten in the 12th century with treatises by Ephrem the Syrian. It is one of the four great uncials, and its underlying text was famously deciphered by Constantin von Tischendorf in the 1840s.

Contains an almost complete text of the Catholic and Pauline epistles. The manuscript features scholia at the foot of the pages attributed to John Chrysostom, and the uncial text is separated into paragraphs by comments written in minuscule script.

It contains large lacunae in Acts 1:1-8:10 and in Hebrews 13:10-25.

Uncial 049 is a 9th-century Greek New Testament codex containing the Acts of the Apostles and the Epistles with numerous lacunae.