Watch List notes:

Turkey, Constantinople, aluminium '40' token, unknown date, U.F. CONSTANTINOPLE within oak wreath, rev. mark of value, certified and graded by NGC as Mint State 63
The oak wreath on the obverse bears a strong resemblance to that on the coins of 19th century France, so perhaps this token was produced by one of the French communities based in Constantinople at the turn of the century.

Estimate: 40 - 60 GBP