These are sickle blades.
They are from Tell el-Yahudiya (Leontopolis). Farmworkers used sickles throughout Egyptian history to cut crops like barley, emmer wheat and flax. The wooden handle had a cutting edge of small, serrated flint blades. Specialist stone workers may have made the flint blades and traded them with the landowners and labourers. The sharp edge would blunt quickly so the labourers would need to sharpen the blades or replace them with sharp new blades they had as spares. These are sickle blades. They are made from flint. They are between 3,800 and 5,100 years old, dating to the 1st to 12th Dynasty (3100-1795 BCE) in the Early Dynastic Period, Old Kingdom, First Intermediate Period or Middle Kingdom.