I installed this Viking C-500 controller plus a Viking K-1700-3 access telephone to control the electric entry gate to my property. I am extremely pleased with the result. The C-500 is exceptionally powerful and flexible, and can be programmed to handle almost any conceivable entry control situation. It has so many options that learning to program it can be a bit challenging and requires several readings of the owners manual. The results are worth it in my opinion. I’m very impressed with the cost-effectiveness of the Viking products. All the other entry control options that I looked at were many times more expensive. I’m very happy with my choice.