4x Sand Eraser + 4x Sand & Rubber Eraser, Color: Gray, White Size: 68x16x10mm, Weight: 30g. It is very efficient for erasing pencil, fountain pen, gel pen, ball point pen. Used for erasing pencil, clean and no trace. Gray Sand Head: Used for erasing fountain pen, gel pen, ball-point pen etc. It is moderate size, comfortable hand feeling. Fine sand particles reduce the damage for paper. It consists of Special formula, natural rubber material, non-toxic and environmentally friendly.