Mersen FB Series disconnect switches are extremely durable, manually operated, fusible disconnect switches. They employ double break contacts per pole that ensure complete isolation of the fuse when the switch is in the OFF position. With safety in mind, all fusible disconnect switches are supplied with fuse covers and line side shrouding as a standard feature. These switches provide the ultimate in short circuit protection when used with Mersen's Class CC, J or L fuses.These heavyduty switches are designed with the most up-to-date disconnect fuse and switch technology available. Designed to meet the UL98 or UL489 standard, the fusible disconnect switch gives you the product that "makes and breaks" power circuits under load. They have been tested and approved for use in the most demanding applications, such as "Service Entrance." The optional TEST function (up to 400 A) enables testing of the control circuit auxiliaries without switching the main contacts. This function provides a simple alternative to a separately wired push button. A wide array of handles are available to meet OSHA padlocking requirements, NEMA configurations, defeater options and NFPA 79 requirements. Features: Service entrance rated; Defeatable pistol handles automatically re-latch when panel door is closed - no tool necessary to reset latch; Modular switch configurations, special executions on request (5-pole, mix ratings.); Front and side operated switches with snap-on auxiliary contact feature; Padlocking feature as standard on modular switchgear boxes; Compact footprints; Padlockable handle; Flange-mounted actuators; 14AWG power taps on both line and load sides for control power transformers or surge protection; External or direct operation handles; Double break contact per pole up to 800 A; Touch safe covers protect fuse terminals; Test positions available up to 400A