Works with any Aladdin 12" diameter paper or parchment shade. For any Aladdin lamp made since 1917: Models 7-12, A, B, C, 21, 21c, 23, 23A, MAXbrite. Brass. Center ring is 2 1/16". Fits under the burner, not under the gallery. IMPORTANT: Aladdin tripods do not fit other brands. Not recommended for glass shades - use a shade ring instead.