On 11 April, 1918, submarine chaser SC 354 was readying for live ASW operations, and a shipment to the chaser was prepared for crosses, drums, and cones, shape signals for use on the hunt.

Subchasers in WWI hunted in units of three: a unit leader and two wing boats. Ship-to-ship communications took several forms, from the radio telephone to the Bearing Indicator. Shape signals were three-dimensional shapes, two feet tall, suspended during hunts. In the photo overlay, the "cone" fully raised signifies "underway." (Inverted, it would be the "top" shape.)