Exodus 28:31-35

31And thou shalt make the cloak of the ephod all of blue.

32And its opening for the head shall be in the midst thereof; there shall be a binding of woven work at its opening round about; as the opening of a coat of mail, it shall be in it — it shall not rend.

33And on the skirts thereof thou shalt make pomegranates of blue, and purple, and scarlet, round about the skirts thereof; and bells of gold between them round about:

34a golden bell and a pomegranate, a golden bell and a pomegranate, in the skirts of the cloak round about.

35And it shall be on Aaron for service; that his sound may be heard when he goeth into the sanctuary before Jehovah, and when he cometh out, that he may not die.