A device for using technical equipment underwater includes at least one guide rail configured to extend vertically underwater on an edifice from above a waterline. At least one device carriage is provided and includes a basic unit having a reception flange configured to couple the technical equipment thereto, and at least one running unit that abuts against the guide rail via guide rollers. A press-on unit is disposed on a first side of the device carriage and includes a lever pivotable on an axis of the device carriage so as to generate a pressing force of the device carriage against the guide rail. The lever includes a support roller at a first end and a weight packet at a second end so as to exert a downward drifting force underwater that is greater than a buoyancy of the device carriage. At least two spacers are each disposed at a first end on the at least one device carriage and abutting the edifice at a second end. A veering and hoisting device is detachably connectable with the device carriage via a coupling device, and is configured to control deployment and retrieval of the device carriage.