Lowrance X37TX Installation And Operation Instructions Manual page 26

Bolt
Washer
Portable transducer assembly: rear view (left) and side view (right.)
Clean the chosen area of the hull before attaching the suction cup.
Locate the transducer on the hull as shown in the following figure.
Don't allow the bracket to extend below the hull, because water
pressure against it can cause the suction cup to come off at speed.
Moisten the cup, then press it onto the hull as firmly as possible. Tie
the nylon cord to the boat and route the transducer cable to the sonar
unit. Your portable sonar is now ready for use.
Portable transducer installed on boat transom.
NOTE:
For optimum operation, the portable transducer should be adjusted
so that it is parallel to the ground. For more information on this,
see the earlier segment on Transducer Orientation and Fish
Arches.
Tie
nylon
cord
here
Suction
Nut
Washer
Transducer
Suction
cup
Hull
cup
22
Screw
Bracket
Transducer