Schlage L0170 06L 612

A: Typically for a 1-3/4" door you would use a 1-1/4" cylinder. However the cylinder length can and will change depending on your door thickness, the hand of the door and the bias at which the doors installed in the center of the door meaning is it centered or is it unequally positioned somewhere in the thickness of the door. Best path forward is to not guess in contact us for guidance. Please also note: The 30-001 used with Rose trim on double cylinder applications requires a Blocking Ring part number 36-082 012 thickness, 1 per side.

The image as seen here: albeit out of date, can be helpful to determining the length of cylinder provided:

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