Printing on side states, "MAY61". Included note states, "Two Experiments ---The installation of a ventilation system, indicated by the "chimneys", permitted 500 man shafts of work to be accomplished on the submarine Picuda (SS382) during the sandblasting and painting period. Previously no other work was performed during this period. Incident to the ventilation system is the enclosed air-lock accessed (right). The complete canvas all-weather cover permitted sandblasting and painting to continue without interference from rain, dew, and fog. Work that normally requires ten to twelve days was completed in seven."
