Plus Guard Your Id Roller Stamp, White Helps prevent identity theft by permanantly blocking out addresses, account numbers etc. so junk mail can be recycled instead of shredded Encrypted pattern in combination with oil based ink penetrates non-glossy papers so personal information cannot be seen at the front or back Retractable roller makes it easy to store - no mess! Not for use on glossy or coated papers as oil based ink may rub off Ink lasts for 160 feet - replaceable ink cartridge (sold separately) is easy to switch out