Insulated ring for M5 studs, 14-16 AWG
The 2-165655-1 is the M5-stud, 14-16 AWG member of TE's PIDG insulated ring terminal line, colour-coded blue for the wire range. Tin-plated copper contact, 0.031" (0.79mm) thick, with a polyamide insulation sleeve that accepts wire insulation diameters from 0.115" to 0.170" (2.92mm to 4.32mm).
Same stud size, different insulation
The Solistrand 1377172-7 also fits an M5 stud and 14-16 AWG at the same 0.031" (0.79mm) thickness, but is non-insulated and shorter — 0.636" (16.15mm) overall vs 0.844" (21.44mm) for the PIDG 2-165655-1. The insulated barrel on the PIDG adds length and provides strain relief at the wire entry; the Solistrand relies on a brazed seam and serrated termination for grip.