A hat having chin strap members comprising: a main hat portion and a brim , the main hat portion having an inside surface and an outside surface, with a frontal reference point and a rear reference point ; a band disposed around a bottom portion of the inside surface of the main hat portion ; characterised by having a first cord having a first end attached to a frontal right-side attachment zone in the band and a second end attached to a rear right-side attachment zone in the band ; a second cord having a first end attached to a frontal left-side attachment zone in the band and a second end attached to a rear left-side attachment zone in the band ; a first chin strap member connected to the first cord ; a second chin strap member connected to the second cord ; a first locking member attached to the first chin strap member ; and a second locking member attached to the second chin strap member ; wherein the first cord and the second cord have a cross section substantially circular; the first chin strap member and the second chin strap member have a slidable movement along the respective outer surfaces of the first cord and the second cord ; and the first chin strap member and the second chin strap member are connectable between the first locking member and the second locking member and are further adjustable for positioning beneath the chin of the wearer; and a ratio d1:L is equal or superior to 11.0:29.5, wherein: a) d1 is a length of the arc from the frontal right-side attachment point to the rear right-side attachment point or a length of the arc from the frontal left-side attachment point to the rear left-side attachment point ; and b) L is a length of the arc from the frontal reference point to the rear reference point . a main hat portion and a brim , the main hat portion having an inside surface and an outside surface, with a frontal reference point and a rear reference point ; a band disposed around a bottom portion of the inside surface of the main hat portion ; characterised by having a first cord having a first end attached to a frontal right-side attachment zone in the band and a second end attached to a rear right-side attachment zone in the band ; a second cord having a first end attached to a frontal left-side attachment zone in the band and a second end attached to a rear left-side attachment zone in the band ; a first chin strap member connected to the first cord ; a second chin strap member connected to the second cord ; a first locking member attached to the first chin strap member ; and a second locking member attached to the second chin strap member ; wherein the first cord and the second cord have a cross section substantially circular; the first chin strap member and the second chin strap member have a slidable movement along the respective outer surfaces of the first cord and the second cord ; and the first chin strap member and the second chin strap member are connectable between the first locking member and the second locking member and are further adjustable for positioning beneath the chin of the wearer; and a ratio d1:L is equal or superior to 11.0:29.5, wherein: a) d1 is a length of the arc from the frontal right-side attachment point to the rear right-side attachment point or a length of the arc from the frontal left-side attachment point to the rear left-side attachment point ; and b) L is a length of the arc from the frontal reference point to the rear reference point . a) d1 is a length of the arc from the frontal right-side attachment point to the rear right-side attachment point or a length of the arc from the frontal left-side attachment point to the rear left-side attachment point ; and b) L is a length of the arc from the frontal reference point to the rear reference point . <EOS>