SB Dunk Low 'Grateful Dead Bears Opti Yellow' (2020)Shop the Nike SB Dunk Low 'Grateful Dead Bears Opti Yellow' (2020). The Nike SB Dunk Low Grateful Dead Bears Yellow is now available on Pushas thanks to a collaboration between Nike Skateboarding and the iconic psychedelic rock group Grateful Dead. The Grateful Dead Bears are a group of stylised dancing bears that Bob Thomas drew and used as the back cover art for the album History of the Grateful Dead, Volume One (Bear's Choice) in 1973. This