Question: The manual for my gate opener is 1500/1600. Will the 636 circuit board work on both models? Answer: Hi Dave, the Apollo 636 is for a dual swing gate operator or the 1600 Model, if you have a single swing gate then you will need the Apollo 635 board. Have questions regarding our products? Our technical sales and support team is standing by if needed, just give us a call at 1-800-730-8382 or contact us by e-mail as we are eager to assist you for all your access control equipment needs. Find the access control product you're looking for today!