Red Seat's No. 20 was replaced by the initials "MV" to honor him. Ahead of the 2020 season, the Red Bulls converted the South Ward into a safe standing section with a rail seating system, similar to the system in place at Banc of California Stadium in Los Angeles. This system allows supporters to watch matches while standing but also contain unlock-able individual red fold-down seats to convert the section to standard seating for international matches and other events. The rails also contain cup holders. The Red Seat was removed and given to the Vallo Family and a new location in Section 101 will be selected to commemorate Mike Vallo. An open standing area was created directly behind the South Ward for supporters to gather while maintaining a view of the field. Red Bull Arena is the third soccer-specific stadium in North America to have a safe standing with rail seating system. On the west side of Red Bull Arena is the "Red Ring of Honor". Established in 2015, the club's 20th season in Major League Soccer, the ring honors the 20 best players in the first 20 seasons of the club as voted by fans. Above the Red Ring of Honor is the retired jersey number "99" of striker Bradley Wright-Phillips; the first to be retired by the Red Bulls. Also above the Red Ring of Honor are listed the years honoring the teams that won the Supporters' Shield in 2013, 2015, and 2018. The lower bowl of the stadium is constructed of concrete, while the upper bowl is constructed of galvanized-metal. The Red Bulls intentionally chose galvanized-metal for the upper bowl so fans could create more noise by stomping their feet. In addition, the main concourse is elevated high, eliminating a majority of field-level entryways. On the North side of the main concourse are 13 "Red Beams"; each one memorializing a special moment in the club's history. In 2017, the Red Bulls opened MLS's first permanent sensory room for individuals and families affected by autism. The space was formerly used as executive offices by the club's general manager Marc de Grandpre, whose daughter is on the autism spectrum. The sensory room overlooks mid-field and features dimmed lighting and lightly-colored walls to offer a soothing environment, along with visual aids, fidget toys and other activities. There is no special ticket or any charge required for use of the room.