I was referring to my shredder manual and noticed it recommended using these to keep the shredder in good working order.
I had been using some shredder oil but found this to be a pretty messy experience, these pouches contain both lubricant and a `grinding powder' which also helps to clean and sharpen the blades.
You get a pack of twelve pouches which depending on how much you shred should last a year, I have started sticking one through a month. They are very easy to use as you just run the whole pouch through the shredder.
After use the shredder does seem happier... the noise from shredding did seem slightly less.
I recommend them and they appear to be good value for money on Amazon.