Timing of the test For all oxygen groups (i.e., Group I, II and III), initial testing must be done within the 30 days before the initial date of service. For Group II beneficiaries, recertification testing must be done between day 61 â 90 after the initial date of service.
Trolling motors are popular with anglers who want to be able to maneuver around a fishing area without disturbing the fish below the surface. When youâre searching for a new electric boat motor, keep these points in mind: 1  Most trolling motors operate on 12 volt, 24 volt and 36 volt circuits.
1 Be sure to measure your boat before buying a trolling motor so that you can choose the correct shaft length. 2  Trolling motors are available with shaft lengths ranging from 36 inches to more than 54 inches. 3  Even the best motors have potential to fail.