The Zyxel USG FLEX 500 is a 1U rack-mount firewall designed for small and medium-sized business networks. Cloud-based security management is combined with malware protection, intrusion prevention, and web and URL filtering. It supports VPN connections via SSL, IPSec, IKEv2, and L2TP/IPSec.

The seven Gigabit Ethernet ports can be configured for WAN or LAN connections. It also features one SFP port, two USB ports, and one console port. The firewall supports up to 500 VPN connections and up to 150 concurrent SSL/VPN connections.

• Type: Firewall
• Quantity: 1
• Form factor: 1U rack-mount
• Gigabit Ethernet ports: 7
• SFP slots: 1
• USB ports: 2 USB 3.0 Type-A
• Console ports: 1
• SPI firewall throughput: 2,300 Mbps
• UTM throughput: 800 Mbps
• VPN throughput: 810 Mbps
• VPN connections: Up to 500
• Concurrent SSL/VPN connections: Up to 150
• VPN tunnels: 300
• VPN support: IKEv2, IPSec, SSL, L2TP/IPSec
• Security algorithms: IPSec, SSL/TLS
• Filtering: Web and URL
• VLAN support: 64
• Power supply: 12 V DC
• Maximum power consumption: 24.1 W
• Input current: 4.17 A
• Built-in fan: Yes
• Noise level: 41.5 dB
• Operating temperature: 0–40 °C
• Storage temperature: -30–70 °C
• Operating humidity: 10–90%
• Storage humidity: 10–90%
• Dimensions: 30 × 18.8 × 4.4 cm
• Weight: 1.65 kg