THEY ARE PRODUCED BY A DIFFERENT SUPPLIER THAN THE 'NON ECO' SERIES. 12 MONTH WARRANTY! HP LASERJET 4200DTN, 4200DTN, 4200DTNS, 4200DTNSL, 4200N, 4200TN, 4200, 4200 LN, 4250, 4250DTN, 4250DTNSL, 4250N, 4250N, 4250TN, 4300DTN, 4300N, 4300TN, M4345MFP, 4345X MFP, 4345XMFP, 4345XM, 4345XM, 4350DTN, 4350TN, 4350TN.
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