These gashapons are more Nendoroid Petite sized than Nendoroid unless you use some clever camera tricks. See photos. Nendoroid and Nendoroid Petite are for display only.
They are by a brand called Toys Spirits. We do not know the original year of release. Each piano was designed to play a song when the keys are pressed, but most of them have dead batteries. They are unopened but old. They all feature fallboards that can be opened and closed to cover or display the keys and the grand piano can be displayed with the lid open or closed using the attached lid hinge.
Two are in a short upright piano style that could be used to represent a keyboard or electric piano as well as a traditional piano. This style comes in black and a cream color. There are also two taller uprights in red and black that have "Spirit" painted on them where the piano manufacturer's name is often printed on a piano. Finally, there is a baby grand.
NOTE: All are in unused condition, but due to their age we can not guarantee that the music will work. Grand piano: Legs are held in place with pegs that pop out easily so gluing the legs in place would be recommended. Red Tell Upright: Some of these appear to have a bit of sticky residue on the underside of their fallboard (the keyboard cover).