Pencil clip fits onto standard-sized office and school pencils (approximately 1/4" diameter). Band can be slightly expanded or compressed. The band also can be placed on the pencil ferrule (metal piece holding erasers to the pencil) if the pencil itself provides insufficient surface to secure the clip--as in triangular-shaped pencils and some of the newer 1/64" smaller diameter pencils. These reusable DCLIPS is a quality pen/pencil clips are precision manufactured. Its spring clip design firmly grips virtually all standard-sized (1/4" to 5/16" diameter) office and school pens and pencils. The finger-operated spring action clip opens to about 1/16" so that you can clip it to your shirt pocket easily. Also great to clip on your note pad or clipboard. Not recommended for extra slim pencils smaller than 1/4" diameter. Unconditional money-back guarantee. Return for full refund within 14 days if you are not completely satisfied.