The Getting Started Guide says that all Printrbots currently ship with 0.4mm nozzles.
The convention for identifying nozzles is based on notches (or "rings") cut into the sides (vertices) of the hexagonal brass "nut".
No notch = 0.5mm
1 notch = 0.4mm
2 notches = 0.35mm
Printrbot Plus operational January 2013
Brass threaded rods (5/16" X 18) & nuts for Z axis
GT2 belts & pulleys
Cable chain to reduce probability of fatigue failure in wires
E3D V5 Hot End, 0.4mm nozzle, also 0.8 and 0.25 in use occasionally
PB fan mount + 40mm fan -- using printed mount adapter, not the E3D supplied fan
Injection molded extruder gears
Optical Z "endstop" (custom designed and built)
Have used many pounds of T-Glase filament. Now also doing some work with Ninjaflex SemiFlex
Print on glass with Scotch Craft Stick or other glue stick