The Von Duprin 47448783 is the OEM double cylinder module service kit for the 2SI option on 98/99 Series exit devices. It ships with the slider assembly, endplate, and security indicator mechanism - the three components that make up the replaceable 2SI module. Cylinder is not included and must be sourced separately. Finish must be specified at time of order because the indicator components are externally visible on the inside door face.

The 47448783 is a service kit - not a conversion kit. If the installed device does not already have the 2SI option and needs to be converted to it, a different part applies. The 47448783 replaces the 2SI module on a device that already has this configuration.

What the Von Duprin 2SI Option Does

The 2SI adds two things to a standard 98/99 Series exit device simultaneously. First, it installs an inside key cylinder on the push side of the device, so the push bar can only retract the latch when that cylinder is in the unlocked position. Second, it adds a security indicator - a 1/2-inch by 1/2-inch metal flag at the head of the device that shows the lock state from inside the room without testing the hardware.

When the flag is visible from inside, the device is unlocked and the push bar operates normally. When no flag is visible, the cylinder is in the locked position and the push bar will not retract the latch. That at-a-glance status makes the 2SI more useful than a standard -2 double cylinder configuration, which provides inside keyed control but gives no visible feedback on whether the device is actually in the locked or unlocked state.

Schools and hospitals are where 2SI gets specified most often. A teacher can lock the push bar from inside the classroom and immediately confirm from the indicator that the door is secured, without opening the door or approaching the frame. Stairwell access control in high-rise commercial buildings is another common application, where security staff need to verify floor access status from the stairwell side.

Von Duprin 2SI Parts: Compatible Devices

The 47448783 covers nine 98/99 Series device configurations across all major mounting types: the 98/99-2 Rim, the 98/9927-2 and 98/9927-F-2 SVR, the 98/9947-2 and 98/9947-F-2 CVR, the 98/9975-2 and 98/9975-F-2 Mortise, and the 98/9949-2 and 98/9949-F-2 CVC. Standard and fire-rated variants of each configuration are covered.

The 2SI option is not available for XP98/99 devices, 98/9952, or 98/9950 WDC configurations. It is also incompatible with cylinder dogging (CDSI) and hex dogging (HDSI) because a dogged device holds the latch retracted - the indicator would show a false locked state while the device is actually unlatched.

Von Duprin Module Service Kit: What the Replacement Procedure Involves

Servicing the 47448783 on a rim or vertical rod device requires removing the device from the door, tilting the slider assembly up at an angle to disengage it, removing the old slider assembly and endplate, installing the new ones from the service kit, and reinstalling mounting screws before putting the device back on the door. On mortise configurations, an additional biasing plate installation step is required and some door modification may be necessary at the head of the door prep.

The 47448783 covers eight finishes: US26D/626 satin chrome, US26/625 bright chrome, US10/612 satin bronze, US4/606 satin brass, US3/605 bright brass, 689 aluminum powder coat, US19/622 matte black, and SP313/695 dark bronze. Devices with the 2SI option maintain ANSI A156.3 Grade 1, UL 305, and UL 10C certifications after service.