Here is an amazing 6-piece frameless shower enclosure with pivots, low iron glass, and all brushed nickel hardware. 
Installed in Lynnfield. 

Header with upper and lower pivots

Many people do not like the look of the header and prefer to do their frameless enclosure without it, however sometimes that’s not am option. 

Anytime there is a lot of separate pieces of glass that aren’t near any type of wall to be secured to, they need to be secured on the top. This can be accomplished by using a header as you can see in these photos.