There's no need to throw away used boxes or mailing tubes, thanks to Avery Parcel Labels with TrueBlock technology | TrueBlock labels are completely opaque, covering any old labels or text underneath | You can reuse boxes and tubes, and send a great-looking package | TrueBlock technology means the labels completely cover everything underneath | Label over existing information and re-use boxes and tubes | Ideal for large envelopes, big parcels, mailing tubes and boxes | Bulk pack, great for large volume users | Labels made with paper from sourced from sustainable forests