We used the Staples Mailmate shredder to shred old-fashioned credit card carbons, approx 100 per week for 12 weeks. This is very light paper. (We had to use an old-school credit card swiper until our computerized gear was set up.) The Mailmate died after four months. We had shredded on CD right after purchase just to see if it would work, and it did. That was the heaviest use the shredder ever received.