The Python automatic door opener uses the patented Chain Glide system, with the new enclosed in-line chain. The chain wont rattle around providing for quieter operation. No tensioning or lubrication of the chain is required for the standard life of the opener. There are no greasy chains or exposed wires. The aluminum rail has channels which conceal the chain and wire leads for a cleaner more attractive appearance. The reinforced metal drive sprocket provides longer life and minimal wear on the system. The Python Chain Glide weathers all of lifes ups and downs, with reliable performance even in extreme temperatures.