A Doppler log is often used to measure the speed of ships: it is a device that measures the ship’s speed in relation to the river/sea bed and/or the water. The Doppler log is mounted in steel flanges that are welded to the bottom of the forward bulwark.
De Boer Staal supplied grade D steel plate, and De Boer Snijbedrijf cut the flanges in which the Doppler log is mounted to size.