The Goldline® SP-30 and SP-30D are single-stage electronic temperature controls designed to be direct replacements for electromechanical controls. Each unit is selectable for temperature range (low range -30Â° to 100Â°F, high range 70Â° to 200Â°); heat or cool mode; Â°F or Â°C; differential (1Â° to 25Â°F); and power supply (21 to 27 vdc or vac, 105 to 130 vac, 195 to 250 vac, 50 or 60 Hz). Other features include short-cycling protection and accuracy of ±1Â°F. Independent Energy Inc., 42 Ladd St., P.O. Box 1305, East Greenwich, RI 02818; 800-343-0826 or 401-884-6990; 401-885-1500 (fax).