The Harvard DK28 is a non-dimmable electronic high frequency ballast to run: 1 x 28w 2D Lamp. The DK28 has formerly been known as a DKE28 and a DK28-70 for ASD lamps.

The Harvard DK38 is a non-dimmable electronic high frequency ballast to run: 1 x 38w 2D Lamp. The DK28 has formerly been known as a DKE38 and a DK38-70 for ASD lamps.

The Harvard DK13 is a non-dimmable electronic high frequency ballast to run 1 x 7w, 9w or 11w PL-S, 1 x 10w or 13w PL-C, 1 x 10w or 16w 2D or 1 x 6-14w T5. The DK13 has formerly been known as a DKE13.

The Harvard DK18 is a non-dimmable electronic high frequency ballast to run 1 x 18w PL-C or PL-T lamp