Master Systems are authorized by following manufacturers for APT and maintenance on their VDR/ SVDR systems.
- Danelec
- Netwave
- AMI
- Totem Plus
- Highlander
- Hyundai
- Interschalt McGregor
- Headway
- NSR
- STI
- Sealantern
- Saracom
- Maris
- Brightsky Electronics (BSKY)