Per Shri V.P. Gulati :

The issue in the appeal relates to the classification of the goods which have been described as Waveguides. The Waveguide as described in the technical literature produced by the appellants is as under:

Wave guides may have rectangular or circular cross-section. In practice uniform cross-section is important for the same reason as transmission lines; they are thus easier to manufacture and their properties are uniform and easier to calculate. In fact any configuration of electric and magnetic fields inside a wave guide must be solution of Maxwell's equations. These fields must also satisfy the boundary conditions imposed by the walls of the guide. It is of utmost importance to realise that conduction of energy takes place not through the walls of the guide; the guide walls only confine the energy. Actual energy conduction takes place through the dielectric filling the wave guide, usually air. In wave propagation it is necessary to speak in terms of electric and magnetic fields while discussing the properties of wave guide, unlike in transmission lines when we speak in terms of voltages and current. Moreover because the cross-sectional dimension of a wave guide must be of the same order as wavelength their use is economical at frequencies above 1 GHz.

Some advantages that the wave guides possess over coaxial lines are discussed here. Wave guides are simpler to manufacture than coaxial lines since the inner conductor is missing. Because there is neither a inner conductor nor a dielectric in a wave guide flash over is less likely to occur. Therefore, the power handling capacity of wave guide is more, and may be about ten times as high as that of coaxial air dielectric rigid cables of similar dimensions. In a wave guide the propagation is by reflection from the walls, power losses in wave guides are lower than in comparable transmission lines.

2. The learned lower appellate authority has held the goods to be assessable under Tariff Heading 8544.11. The revenue (appellants/respondents) is aggrieved of the classification as held by the learned lower authority and the classification sought is under Tariff Heading 8307 or in the alternative 7411. The importers (appellants/respondents), however, seek re-classification of the goods under Tariff Heading 8529.90. Various competing entries as above are reproduced below for convenience of reference:

3. The learned lower appellate authority has examined the issue taking into consideration the use of the goods imported and in terms of the interpretative Rule 4 has held the goods would be classifiable under Tariff Heading 8544.11. The learned lower authority's findings are reproduced below for convenience of reference:

I find that the Learned Lower Authority has not addressed the question from the angle of the appellant that the impugned waveguides, though in running length, were not capable of being used in any other apparatus or instrument except in transmission apparatus as microwave passive component. Ordinarily for classification purposes, any item or article in running length is not considered as a component, as it is generally understood that a component ought to be tailor-made for being fitted into the main machinery, equipment or apparatus without further processing of the item as such. The underlying presumption of course, is that the article in running length is capable of being used in more than one end product and, therefore, cannot be conside