Space Combat Helmet (5e Equipment)
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Space Combat Helmet
A space combat helmet is a rigid, heavily armored helmet that fully encloses the head. The helmet can lock into place on suits that are either fully sealed or intended to provide vacuum support, providing an airtight seal. The helmet has built-in hearing protection, providing advantage on saving throws against being deafened by loud noises, and a light filter that gives you advantage on saving throws against being blinded by bright light, in addition to allowing you to see in the infra-red spectrum. Lastly, the helmet includes a radio transmitter and reciever, allowing you to communicate over a certain frequency (usually specific to a particular organization or unit) over a range of 20 miles.
Partial armor only grants its AC bonus if you are wearing light or no armor. If you are wearing only one piece of partial armor, you are still considered to be wearing your base armor type (e.g. no armor or light armor). If you are wearing two or three pieces of partial armor, you are considered to be wearing the heaviest type of partial armor worn (e.g. medium or heavy armor). You cannot wear four or more pieces of partial armor.