Total length : 187mm
Head length : 73mm
Stick length : 114mm
Diameter :
Empty weight : 750gram

Photos and info © Dr. Ruby.

See the two photos below, nice observation by Dr. Ruby :
He already had this nice wrist-compass with good factory stamps, but also found an RGD-33 practice grenade with exactly the same markings.

The factory "Завод учебных приборов" (abbreviated as " ЗУП N1 ") is the "Factory of educational devices", or also called "The training kit factory under the Artillery department of RKKA".
There is also a factory with the same markings but has "N2" mrked, instead of "N1".