. Watchguard Web Blocker is a fully integrated 1-year security subscription for all Watch Guard Firebox M400 Firewall appliances. It allows IT administrators to manage web access & content for stronger security & control of web surfing. Web Blocker blocks malicious sites to keep your network protected from risky web content. It helps conserve network bandwidth prevent legal liability from inappropriate content & increase employee productivity while it guards the network against malicious attacks from rogue websites. & because Web Blocker is integrated with the Watch Guard security appliance you have an easy-to-manage cost-effective solution with no additional hardware to buy..