If you want the dimensions of the unit itself, you can find them in
the 505 Wiki entry.
But more likely you need to know the specifications for the box it ships in, including all packaging.
The box mine came in is approximately 6" wide x 8.5" tall x 1.75" deep. Unfortunately, I don't know its weight when it has the reader inside with all packaging, but since the reader itself is 9oz, I'm sure it can't be over 1 lb. Maybe someone else will know.
(Rather amusingly, Amazon lists its shipping weight as 7 lbs., but that makes no sense. Do they ship it with 6.5 lbs of packaging?)