Heavy Duty Industrial Curtain Trolley with Steel Wheels. The steel wheels on steel bodies are recommended for curtains weighing more than 100 pounds or over 15 feet tall. These rollers are compatible with the 16RT tracks. The 1.5 inch steel plate extends below the track and offers a 0.38 inch diameter hole to accept chain or hook. Pull Rope Trolleys, recommended for curtains over eight feet tall.