Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bell Telephone MfgfiledCriticalBell Telephone Mfg
Priority to BE611360ApriorityCriticalpatent/BE611360R/en
Application grantedgrantedCritical
Publication of BE611360RpublicationCriticalpatent/BE611360R/en