Polaris L4N-14 CMP Lug Cu Long 4 AWG 1/4 Blt 1 IN Spc
https://testing.nsiindustries.com/product/4-awg-1-4-2-hole-copper-long-lug-gray-3/
The POLARIS compression design creates a permanent, vibration-resistant connection that you can rely on with low contact resistance. Suitable for a wide range of applications, including power distribution, grounding and data transmission.