The Schlage XB13-379 is the OEM ADA thumbturn rim cylinder with horizontal tailpiece, designed for installation on the inside head of the Von Duprin 98/99 Series -2 (double cylinder) exit devices. Available in 626 Satin Chrome only - no finish substitution is available for this part. The XB13-379 is documented in the Schlage Key Systems Cylinders and Keys Catalog and is specifically recommended in the official Von Duprin 2SI Data Sheet (document 116039) alongside the XB11-979 and 20-021 rim cylinders for double cylinder exit device applications.

When installed on the inside head of the 98/99-2 device, the XB13-379 ADA thumbturn controls the lock state of the outside lever, thumbpiece, or knob trim. Rotating the thumbturn locks or unlocks the outside trim from inside the room - giving authorized occupants inside control over outside access.

What the Horizontal Tailpiece Means on the XB13-379

Standard rim cylinders have tailpieces that exit the back of the cylinder in line with the cylinder body - a vertical orientation in the normal installed position. The XB13-379 has a horizontal tailpiece - the tailpiece exits perpendicular to the cylinder centerline. This specific geometry allows the XB13-379 to align with the inside mechanism of the Von Duprin 98/99-2 exit device's inside cylinder position, where a vertically oriented tailpiece would not correctly engage the latch control mechanism.

This horizontal tailpiece distinction is also relevant for the -2SI (double cylinder with security indicator) configuration. The official Von Duprin 2SI Data Sheet notes: "Cylinders with vertical tailpiece required. To accommodate cylinders with horizontal tailpiece, order 47686979 kit for compatibility." If installing the XB13-379 on a 2SI-equipped device, the 47686979 horizontal tailpiece compatibility kit is required in addition to the cylinder itself. For standard -2 double cylinder installations without the 2SI option, the XB13-379 installs directly without the additional compatibility kit.

What the Schlage ADA Thumbturn Does vs a Standard Round Thumbturn

The ADA thumbturn on the XB13-379 is a different design from the standard round thumbturn cylinder. The ADA Standard for Accessible Design requires that operable hardware must be usable with one hand, without tight grasping, pinching, or twisting of the wrist. Standard round thumbturns fail this requirement - they require a finger-tip grip to rotate and cannot be operated easily with a closed fist or palm.

The XB13-379 ADA thumbturn uses a wing or lever-style design that can be operated by pressing with the side of a hand, using a closed fist, or with limited hand function. This makes the XB13-379 the correct cylinder specification for accessible facilities, behavioral health applications, and any installation where ADA compliance for inside door controls is required.

Schlage Thumbturn Cylinder Family: XB13-379 vs XB11-979

The Von Duprin 2SI data sheet lists two Schlage thumbturn rim cylinders for the -2 and -2SI applications - the XB11-979 and the XB13-379 (this product). Both are ADA thumbturn rim cylinders. The distinction is in the tailpiece format: confirm which tailpiece orientation the specific inside head installation requires before selecting between them.

For cylindrical lock and exit device cylinder applications requiring standard keyed rim cylinders rather than thumbturns, the Von Duprin 2SI data sheet recommends the Schlage 20-021 rim cylinder.