The GDA series is a marine crane that mainly handles sand and gravel (aggregates).
In 1956, Shikoku Kenki Corporation (now SKK) manufactured the first marine crane to become the prototype of GDA.
Through the efforts in research, development and improvement, it became the current GDA.
The crane of the GDA series is additionally equipped with a drum only for hook-service (the third drum), it is possible for load lifting work while fitted with a grab bucket.