Turntable pit requires sunken installation for flush mount on layout. 8 spoke tracks on outer edge. Can be expanded to 24 spoke tracks with 8997 extension set. Extensive details and prototypical paint work. Turntable operated by remote control using control box included with unit. Electric motor mechanism. Automatic shutoff of power to all tracks not in contact with the deck. External turntable diameter 170 mm / 6-11/16*. Deck length 132 mm / 5-3/16*. Flush mount installation requiring 145 mm / 5-3/4* diameter hole. Can be used with 8983 locomotive shed.