3603306 is referenced by 18 patents and cites 4 patents.

The improved snorkel (FIGS. 1-4) in contrast to the prior art snorkel (FIG. 5) is shaped and designed to fit closely to the face of the wearer whereby viscous drag is minimized. Unnecessary curves in the snorkel tube are eliminated whereby minimum resistance is encountered to water being purged from the snorkel by exhalation. The feathered edge (FIG. 3) also assists in this function.

Title
Snorkel
Application Number
05/031,809
Publication Number
3603306
Application Date
April 9, 1970
Publication Date
September 7, 1971
Inventor
Bonin Jr Richard J
Assignee
Under Sea
IPC
A63b 07/00
B63C 11/20
B63C 11/02
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