Goalie neck protectors come in two different forms, shields and bibs. Shields are clear plastic guards that are tied onto a goalie's helmet. Bibs are special padding that a goalie straps around their necks under their chest protectors.
Different goalies have different preferences between bibs and shields and have many pros and cons to consider.
Benefits of Shield
Benefits of Bib
More protective power
Doesn't restrict vision at all
Can not interfere with chest protector
Doesn't hinder head movements
Usually less expensive
Can't fall off during game
Better throat coverage
More coverage of collarbone and chest
Goalies also do not have to choose just one type of goalie neck protector. Many goalies use both a bib and a shield. At the end of the day, the goalie's comfort and preference are the most important factors.
Goalie neck protectors can be bought at most hockey goalie equipment stores. Different types of hockey goalie neck protectors cost different amounts. Shields typically cost about $30-$50. Bibs typically cost $40-$60, but can cost as much as $100 if they cover the chest area too.