An insect screen for boats, particularly for portholes and manholes, has a rigid frame that supports a rigid mesh and embeds an opposite pair of plate-like lobes that jut out from its internal edge and are provided with through holes crossed by respective bars that slide and revolve relative to the holes. Each bar is provided at one end with a hooked end section, folded at right angle, whereas the other end is associated with a knob that is subject to the thrust of a helical spring externally inserted on each bar in intermediate position between the knob and the lobes.

A cockpit covering system for a small boat comprises a tent or cover comprising a plurality of wall portions and a base, and wherein the tent is sized to extend over a recessed area of a cockpit and to enclose an interior that extends from above deck height to below the height of a base layer. A compressible gasket is below the base for resting on a deck of the small boat around the cockpit outer perimeter. A plurality of webbing straps extend from the outer perimeter of the boat to the tent. A plurality of webbing straps extend from the cockpit outer perimeter to the tent covering system. Tension applied to the plurality of webbing straps compresses the compressible gasket to form a seal along a cockpit recessed area. Pole housings can be provided on webbing straps or on the tent base to secure tent poles at deck level.