23 Sep 1937
Harry Jeffra beats Sixto Escobar via unanimous decision 15/15
Bantamweight (118 lb)
Harry Jeffra becomes the NYSAC, RING and WBA Bantamweight world champion
20 Feb 1938
Sixto Escobar beats Harry Jeffra via unanimous decision 15/15
28 Sep 1939
Joey Archibald beats Harry Jeffra via split decision 15/15
Featherweight (126 lb)
20 May 1940
Harry Jeffra beats Joey Archibald via unanimous decision 15/15
Harry Jeffra becomes the NYSAC and RING Featherweight world champion
29 Jul 1940
Harry Jeffra beats Spider Armstrong via unanimous decision 15/15
12 May 1941
19 Jun 1942
Chalky Wright beats Harry Jeffra via knockout 10/15