These are lego compatible technic bricks. The models here are only a selection for convenience.
All length sizes can be configured on the Perfect Printable Bricks website. If these don't fit quite right with your legos you can fix that with the calibration bricks. And using the modifiers on the ppBricks website.
Naming scheme is a/o + length in studs. a has the holes aligned with the studs and o has the holes offset from the studs
Other lego compatible stuff
The author marked this model as their own original creation.