The replacement for the D871 is the D271. None of the parts are backwards compatible.
D271 description:
Thumbturn x Occupancy Indicator Deadbolt thrown or retracted by turn unit only. Occupancy indicator on outside (reads either "in use" or "vacant" with color coding). Bolt automatically deadlocks when fully thrown.INFORMATION PROVIDED THROUGH THIS SITE IS PROVIDED TO YOU AS IS WITHOUT ANY EXPRESS REPRESENTATIONS OR WARRANTIES OF ANY KIND, AND WE MAKE NO REPRESENTATION OR WARRANTY THAT THIS SITE(OR ANY INFORMATION PROVIDED IN RESPONSE TO YOUR INQUIRY), WILL BE ACCURATE, COMPLETE, OR ERROR-FREE.
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