Guide structure (100; 200; 300; 400) for a chain (Cn) for an article conveyor, said guide structure comprising: a guide portion (105; 205; 305; 405) for guiding the chain along a first direction identifying a direction of movement of the chain, wherein the guide portion has a guide portion first surface (105u; 205 L; 305 L; 305'u; 405u) that, in use, faces the chain, and a guide portion second surface ( 105 L; 205u; 305u; 305' L; 405 L) opposite the guide portion first surface, and wherein the guide portion comprises at least two rails (115;; 215;; 315;; 415';) each one extending, along a second direction orthogonal to the first direction, from the guide portion first surface to a guide portion third surface (115;w; 215;w; 315 i W; 415 i W) that, in use, faces the chain, each pair of rails delimiting, along a third direction orthogonal to the first and second directions, a respective guide channel (120 j; 220 j; 320 j; 420 j) for at least partly accommodating the chain, each guide channel having side walls formed by side walls (115 i S1,115 i S2; 215 i S1,215 i S2; 315 i S1,315 i S2; 415 i S1,415 i S2) of said pair of rails and a bottom wall forming said first surface, and a base portion (110; 210; 310; 410) for supporting the guide portion, the base portion having a base portion first surface (110u; 210 L; 310 L; 410u) that, in use, faces the guide portion second surface, and a base portion second surface (110 L; 210u; 310u; 410 L) opposite said base portion first surface, wherein the base portion is made of a first material and the guide portion is made of a second material different from the first material, wherein the guide structure further comprises fastening means (150 S,150 B; 250 S,250 B; 350 S,350 B; 450 S,450 B;) for fastening the guide portion and the base portion to each other at one or more of said at least two rails, characterized in that the guide portion comprises holes (145 GP; 245 GP; 345 GP; 445 GP) extending, along the second direction, into the rails between the first and third surfaces of the guide portion, and wherein said fastening means is adapted to be fitted into said holes and into the base portion for allowing the guide portion to be fastened to the base portion, and in that the holes of the guide portion comprise through holes opening to both said first and third surfaces of the guide portion. a guide portion (105; 205; 305; 405) for guiding the chain along a first direction identifying a direction of movement of the chain, wherein the guide portion has a guide portion first surface (105u; 205 L; 305 L; 305'u; 405u) that, in use, faces the chain, and a guide portion second surface ( 105 L; 205u; 305u; 305' L; 405 L) opposite the guide portion first surface, and wherein the guide portion comprises at least two rails (115;; 215;; 315;; 415';) each one extending, along a second direction orthogonal to the first direction, from the guide portion first surface to a guide portion third surface (115;w; 215;w; 315 i W; 415 i W) that, in use, faces the chain, each pair of rails delimiting, along a third direction orthogonal to the first and second directions, a respective guide channel (120 j; 220 j; 320 j; 420 j) for at least partly accommodating the chain, each guide channel having side walls formed by side walls (115 i S1,115 i S2; 215 i S1,215 i S2; 315 i S1,315 i S2; 415 i S1,415 i S2) of said pair of rails and a bottom wall forming said first surface, and a base portion (110; 210; 310; 410) for supporting the guide portion, the base portion having a base portion first surface (110u; 210 L; 310 L; 410u) that, in use, faces the guide portion second surface, and a base portion second surface (110 L; 210u; 310u; 410 L) opposite said base portion first surface, wherein the base portion is made of a first material and the guide portion is made of a second material different from the first material, wherein the guide structure further comprises fastening means (150 S,150 B; 250 S,250 B; 350 S,350 B; 450 S,450 B;) for fastening the guide portion and the base portion to each other at one or more of said at least two rails, characterized in that the guide portion comprises holes (145 GP; 245 GP; 345 GP; 445 GP) extending, along the second direction, into the rails between the first and third surfaces of the guide portion, and wherein said fastening means is adapted to be fitted into said holes and into the base portion for allowing the guide portion to be fastened to the base portion, and in that the holes of the guide portion comprise through holes opening to both said first and third surfaces of the guide portion.