400
Why would Heber's wife betray him and kill their ally by hammering a tent peg into his head?
Heber and his wife were descendants of Moses' father in law. They were originally friends of Israel. Heber had picked up his family and moved to the north to join up with Jabin. Heber's wife, Jael obviously was not on board with Heber's decision and was still a friend of Israel.