A method of making a gas treatment device, the method includes projecting a laser line onto a side of substrate from a laser line generator angled away from a viewing source; projecting a laser dot onto the substrate from a laser dot generator located above the viewing source; verifying an alignment of the substrate with at least one of: another substrate and a housing by comparing the laser line projection on the substrate to the laser dot projection on the substrate, wherein the alignment is verified when the laser line projection and the laser dot projection are co-linear; and stuffing the substrate into the housing.