ɹˈaʊnd plˈæstɪk ɹˌɛtɹoʊɹᵻflˈɛktɪv bˈʌʔn̩z mˌeɪd ʌv tɹænspˈæɹənt plˈæstɪk ɑːɹ plˈeɪst ɪn ɹˈoʊz fˈɑːloʊɪŋ ðə kˈɑːntʊɹz ʌv sˈaɪn lˈɛdʒənd ˈɛlɪmənts, jˈuːʒuːəli pˈeɪntᵻd wˈaɪt, sˈʌtʃ ɐz lˈɛɾɚz, nˈʌmbɚz, ˈæɹoʊz, ænd bˈoːɹdɚz.
Round plastic retroreflective buttons made of transparent plastic are placed in rows following the contours of sign legend elements, usually painted white, such as letters, numbers, arrows, and borders.