7/16" high by 1-1/8" long. Blade comes in 3 choices, .050, .080 or .125. The Base comes in 3/8" dovetail and 3/32" or 1/16" thick brass. It is recommended to use the 3/32" base for ROUND barrels. If you would like the 1/16" thick base, put that in the comment section please.

Rectangular Blade Front Sight