The SD visor range. Left to right, these are the:

SD Platinum full-face visor
SD half-visor Mk2
SD Mask-visor see also SD Mask-visor test reports
SD Standard full-face visor

See also:

SD head-frame options
Goggles

Polycarbonate degrades in sunlight so we recommend that visors should usually be replaced each year - a recommendation also made by UNMAS (see Section 11 in this link to a PDF of an UNMAS Technical Note for Mine action (TNMA).