The Sargent 746 ETL key retracts latchbolt is a 700 Series ET Freewheeling trim where key unlocks trim, trim retracts latch and trim relocks when key is removed.   #41 Cylinder Supplied.   For use on 80 Series exit devices.

Sargent 80 Series catalog

Freewheeling Trim

The lever rotates when the door is locked preventing excessive force from being applied to the horizontal lever.

Suffix - Determined by Exit Device (See Below)

No Suffix

Square Spindle or No Spindle for inactive functions for all 8900, 8300, 8700 with bottom rod and 8800, 8500, NB8700, PP, PR & SP8700 devices with these functions: 04, 10, 16, 40 & 44

-4 Suffix

Offset Mtg Tabs Top & Bottom for all AD & MD8400 and AD, WD & MD 8600 devices

-6 Suffix

Offset Mtg Tab Top Only for all PP, PR, SP, LP, LR & LS 8600 devices

-8 Suffix

Cross Type Spindle for 8800, 8500, NB8700, PP, PR & SP8700 devices, except with these functions: 04, 10, 16, 40 & 44