Of course the A-26 Invader originally had round tipped Ham Standards for it's B-Series R-2800's. Then for counter-insurgency work in places like Viet Nam they were upgraded with C-Series R-2800 and were equipped with what looked like very much like the square-tipped Ham Standards from the DC-6.
Some years before I had seen A Martin B-26 Marauder converted to executive use which also had been upgraded with C-Series R-2800 and the large paddle-bladed square-tipped Ham Standards.. -