Short Tow - under 200 metres (measured stern to stern).

Long Tow - tow over 200 metres.
Here towing vessel less than 50 metres in length.
Here towing vessel possibly more than 50 metres in length.

Rear View - Stern Lights on each. Towing Vessel also has yellow towing light.

Submerged or Inconspicuous Tow
towed vessel less than 100 metres
towed vessel more than 100 metres
towed vessel width more than 25 metres - also has lights each side, (Nearly rear view).

Restricted Manoeuvrability - here towing vessel possibly more than 50 metres, tow more than 200 metres.