Eagle on a baroque shield - Surcharged

Stamp type I: Two dashes of different length behind the right F.
Surcharge type I: "I" above the other words

Country:	Poland
Type:	Postage stamps
Series:	1st Polish Stamps Exhibition in Warsaw
Nominal:	15+5 Polish fenig
Year:	1919
Material:	medium, white, smooth (x) or horizontally ribbed (y) or vertically ribbed (z)
Size:	21 x 26 mm
Perforation:	line 11½
Mintage:	2,600,000