Originally posted by sigfreund:
The most obvious way to distinguish between DAK and old style DAO is by the hammers.
Below, left to right: common DA/SA hammer; “sport” DA/SA hammer; DAO hammer; “bobbed” DAO hammer; DAK hammer.
The bobbed DAO hammer is uncommon, but as pictured does not have a spur. Its shape is obviously somewhat different from the DAK’s.
Pistol with DAK hammer.
It is usually not possible to determine by external appearance of the hammer whether it’s DA/SA or DAO, but of course a DAO pistol will not normally have a decocking lever.