1769-1859 Japan 4 Mon with 11 Wave Cash   Edo Ginza Mint Tokugawa Shogunate Kan'ei Coin 

Japanese Kan'ei Tsūhō: The Japanese Shogunate (military leadership) cast Bronze Cash style coins in 4 Mon denomination with two Types:  11 Waves (1769-1859)  most were issued in 1769,  there were 2 additional issues of this same type : Bunsei Coins issue in 1821-1825  and  Ansei Kan'ei from 1851-1854  ,  and also a 1 year type (1768) with 21 Waves on the reverse. 

For more details on this interesting series of Japan Shogunate Cash Coins,  search and see wikipedia article:   Kan'ei Tsūhō