Late model Campagnolo Super Record crankset without the fluting on the crank arm.
Many of the examples I have found have a date code of 21 inside a square, which translates to 1986. Starting in 85 it appears that Campagnolo took on a square with a two digit number inside.  [11] = 1985, [21] = 1986, etc.  [61] was 1990. 
A few of these style cranks still had an engraved style campagnolo logo, there after they used a laser etched logo which often wore off from use.