Exodus 39:19-21

Young's Literal Translation

¹⁹ And they make two rings of gold, and set [them] on the two ends of the breastplate, on its border, which [is] on the side of the ephod within;

²⁰ and they make two rings of gold, and put them on the two shoulders of the ephod below, over-against its front, over-against its joining, above the girdle of the ephod;

²¹ and they bind the breastplate by its rings unto the rings of the ephod, with a ribbon of blue, to be above the girdle of the ephod, and the breastplate is not loosed from off the ephod, as Jehovah hath commanded Moses.