Datasheet

The Quad, like the Proto, has three breakouts for each pin on a Feather,
as well as a bunch of plain grid proto holes. Also, the four sets of pins
are cross connected and for GND and 3.3V, giving you a full strip of
connected pads.
You'll need to solder on the female headers to the PCB, the Quad comes
as a mini kit!
Also available is the Quad FeatherWing as a 2x2 kit for a slightly different
arrangement.
PCB dimensions (unassembled): 95 x 50 x 1.5mm