This bayonet appears to have a unique blade design. I am no expert. As it has a wooden grip I am thinking WW1 or prior.

The blade is 17.5" the overall length is 22.5. I could not find any marking or number on this bayonet.

the scabbard (or what is left of it) is included in the sale.

Please ignore the WW1 German Flare gun.  These are the only photos I have of the knife

Another ebayer suggested that this bayonet is from a 1914 Dutch hemburg carbine