steerer tube markings
 

Fork crown race inner diameter 26.4mm, standard ISO. The steerer tube is stamped, very lightly.

On the front "REYNOLDS 531". That much is obvious.

On the rear <mumble>, perhaps nothing, followed by "LT 16/13".

What is the 16/13? And does the LT mean Light, or something totally different?

The frame is Italian. The threads fit an ISO 1" headset but I can't tell if they are cut as Italian or ISO. Given the 26.4mm diameter above I would expect ISO.

The 16/13 is the gauge, or wall thickness, of the non-butted and butted ends of the steerer tube.

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