USD307961SExpiredUtility
Hot water tank helical coil cleaner
Individually held — no corporate assignee on recordPriority: Feb 25, 1987Filed: Feb 25, 1987Granted: May 15, 1990
Est. expiryFeb 25, 2007(expired)· nominal 20-yr term from priority
Inventors:Edward B. Howell
52
PatentIndex Score
8
Cited by
3
References
1
Claims
Claims
exact text as granted — not AI-modifiedThe ornamental design for a hot water tank helical coil cleaner, as shown and described.
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