沙膠 [－胶]

Jyutping saa1 gaau1
Pinyin shā jiāo

Definitions (粵典–words.hk)
  1. 名詞
    一種​擦​膠​，​比起​一般​擦膠​粗糙​，​多數​用​嚟​擦​走紙​上​嘅​原子​筆痕​，​原本​設計​用​喺​較​厚​較​硬​嘅​紙​上​（​量​詞​：​嚿​）
    rubber used to erase ink; hard eraser
Definitions (Wiktionary)
  1. noun, Hong-Kong
    sand eraser (eraser with a texture of sandpaper, designed to rub off ink by altogether removing the surface of the paper)

沙膠 [－－]

Jyutping saa1 gaau1
Pinyin shā háo

Definitions (CC-CANTO)
  1. an ink eraser