A shredder feeder has a first receiving post configured to receive a roll of first material, second and third receiving posts respectively configured to receive first and second rolls of second material, and a pair of guideposts that form an outlet of the shredder feeder therebetween. The respective guideposts are positioned to respectively direct the second material from the first and second rolls toward the first material from the roll of first material so that the first material is interposed between the second material from the first roll of second material and the second material from the second roll of second material when the first material and the second materials from the first and second rolls of second material pass concurrently through the outlet.