Among international office supply companies, Czechoslovakia's Koh-I-Noor, founded in 1790, is one of the oldest and best. Koh-i-Noor's Combined Eraser 6521 is manufactured with all-natural materials and  has two levels of erasure, use the pink end for the majority of graphite, the grittier blue end is for more stubborn marks.

Single eraser
1.5"