What are the differences between the Von Duprin 47 and 48 latch assemblies?

The following list explains the differences between the Von Duprin 47 and 48 latch assemblies.

• The 47 top latche has 5/8" throw latchbolt.
• The 48 top latch had 3/4" throw latchbolt for devices shipped prior to 6/15/2014.  After 6/15/2014, the top latch will be a 47 top latch and will only have a 5/8" throw latchbolt.
• The 47 bottom latch has a 5/8" throw for use on doors with up to ¼" gap between the bottom of the door and the floor or threshold.
• The 48 bottom latch has a 1 1/2" throw for use on doors with over ¼" and up to ¾" gap between the bottom of the door and the floor or threshold.
• The 48 latch mounting brackets are thicker and have a different hole pattern for mounting the bracket to the latch.
• The 47 top latch is the same latch for both the standard mechanical device and the electric latch retraction device.
• The obsolete 48 top latch had a version for mechanical devices and a different version for the electric latch retraction devices. The bottom side of the old 48 top latchbolt was milled out to allow the latch to retract into the latch case when the device is electrically actuated.

Determining which latch to use comes down to the gap between the door and the floor or threshold under the door when shut (see items 3 and 4 above).