This is a knife bayonet used from the period of about 1923 into and through WWII; it was designed to fit the Czech version of the K98 German Mauser. According to Janzen, "These bayonets were utilized by Lithuania, Iran, and South America" as well as Czechoslovakia.
There are a number of bayonet variants sub-models including short and long versions; also varying finish types, blade positions (upward or downward facing cutting edges) among others.
The most distinct feature about this particular model is that the blade appears to be upside-down (cutting edge on top).
All models have wood grips (with attaching variations), steel pommel, crossguard, and blade.
The scabbard is of blued sheet-rolled-steel.

These bayonets will fit both the Czech VZ23 and VZ24 Short Rifles; variants also were modified for the German K98 Mauser.