From here:
http://www.beastcoins.com/World/Poland/Poland.htm
"Poland, Sigismund III (1587-1632), Poltorak/3 Kruzierz, 1626, Bromberg Mint
· SIGI · 3 · D · G ·-REX · P · M · D · L
Crowned shield of arms, 3 in frame below
· MONE · NO ·-· REG · POLO ·
Imperial orb inscribed with Z4, Z | 6 across fields, donkey head in cartouche below
Plain edge
20mm, 1.20g, Silver
Mintage: Unknown
Kopicki 873; KM 41"
http://www.beastcoins.com/World/Poland/E0695.jpg