Crimp termination and stud fit
The 1577647-1 is the 10 AWG, #10 stud member of TE's PIDG, Strato-Therm ring terminal line. It crimps onto 10 AWG wire and mates with a #10 stud — the serrated termination bites through oxide on the conductor to maintain contact resistance under vibration.
Stud size and wire gauge across the series
Within the PIDG, Strato-Therm series, the 1577647-1's #10 stud and 10 AWG wire gauge sit alongside the 1577649-1 (5/16 stud, same 10 AWG) and the 1577640-1 (10 stud, 12-14 AWG). The 1577639-1 shares the 12-14 AWG range with an 8 stud. All use the same crimp termination and nickel-plated copper contact — the stud size and wire gauge are the selection axes.