Came across this today and had to have it. The shopkeeper selling had just serviced the movement and been wearing it for the last few days to check out the timekeeping - which was and is good.
We think the original strap, which is the softest leather imaginable and it wears really well.
Original untouched dial shows some lume loss on the numerals and from the hands - a few scratches on the glass, which may polish out.
Solid Britannia Silver hinged case with an unhinged case back plus an additional inner hinged dust cover. The hinged dust cover, case back and body each carry a matching serial number.
Nice signed Zenith movement and the serial number would indicate (if my memory serves me right for Zenith is about 1916-18 maybe).
Looks pretty good on the wrist too - and I'm very pleased. I think maybe the crown has been changed at some point in it's 90 odd years - could have been an onion style - but difficult to tell.