The main notable difference of the Gazelle Indoor was the translucent gum sole unit which wrapped around the entire shoe as oppose to the traditional textured white midsole of the OG Gazelle from 1968, the Gazelle II & also the Gazelle 91. The Gazelle Indoor took its "Indoor" inspiration from the Handball Spezial which was released in 1979 as an indoor court performance shoe & also featured the translucent sole unit. Minus the t-toe design, the suede overlays to the heel counter & a slightly sturdier looking sole, the Handball Spezial could quite easily be mistaken for the Gazelle Indoor by a 3 stripes novice. Another notable adidas style which included 'Indoor' in its title was the adidas Indoor Super and although the Indoor Super was a squash shoe and had nothing really to do with the Gazelle story, its intended indoor court use was kind of similar.