This cause closely resembles Rushmore v. Manhattan Works, 163 Fed. 939, 90 C. C. A. 299, 19 L. R. A. (N. S-) 269, where this court considered a case of unfair competition in the sale of automobile lamps. The case at bar is concerned with automobile horns. The resemblance between complainant’s and defendant’s horns is very great. It is difficult to tell the one from the other without an inspection so close as to read the inscription on the name plates. Under the principles of the Rushmore decision, such a manifest imitation in details of construction, with the consequent likelihood of confusion, should be prevented, unless the points of resemblance are the necessary result of an effort to comply with the physical requirements essential to commercial success. A majority of the court are not persuaded that the close resemblance between the two horns results from such an effort. The most characteristic feature is the “right-angled construction,” referred to in the order. Possibly at final hearing defendant may be able to show that a commercially successful power-driven horn of this general type could not be made, unless the shaft which transmits the power is at right angles to the axis of the horn. But the record before the District Judge did not establish that proposition sufficiently to excuse the adoption of this feature of construction, which, probably more than any other single feature, makes the appearance of the two horns so nearly alike.

In the opinion of the majority of the court, the order for preliminary-injunction should be affirmed.