Shell Fuze Timer ?

[siegfreid]

I am assuming this is a timer from a shell fuze ? No markings whatsoever & beautifully made & by the looks of the construction , quite old . Measures 1.65" diameter . Any help appreciated . Siegfreid.

 

[spotter]

I think these are from the older short stumpy version of the 81mm illum mortar rounds,heres one i accuired plus a pic of the round i think it was removed from