Exodus 30:15-17 New Revised Standard Version, Anglicised Catholic Edition (NRSVACE)
15 The rich shall not give more, and the poor shall not give less, than the half-shekel, when you bring this offering to the Lord to make atonement for your lives. 16 You shall take the atonement money from the Israelites and shall designate it for the service of the tent of meeting; before the Lord it will be a reminder to the Israelites of the ransom given for your lives.
The Bronze Basin
17 The Lord spoke to Moses: