AGV has a long and storied history, with riders like Giacomo Agostini, Barry Sheene, Kenny Roberts, Johnny Cecotto, Angel Nieto, Marco Lucchinelli, Randy Mamola and, of course, Valentino Rossi all wearing the brand.
In the early 50s AGV produced the first 100% fiberglass open-face helmet. A Few years later, taking advantage of the experience acquired in creating a special helmet to run the flying start kilometre on skis, AGV developed the first fiberglass full-face helmet.
Since the SHARP test was established in 2007 all of AGV helmets have been rated. None of the helmets have scored below a 4. The S-4 has scored 5 out of 5.
A full range of visors are available, you can find them here. Everything from full black to iridium.