There is confusion on what type of connector is used on the EG4 PowerPro batteries. I was confused and no one I asked knew either.
The EG4-supplied cables are stamped "Degson" on the sides. Clearly they are not Amphenol.
Amphenol SurLok might or might not be compatible with Chinese knockoff Degson.
https://amphenol-industrial.com/products/surlok-plus/
Grok 3 provides some insight into the situation:
https://grok.com/share/bGVnYWN5_4890490f-c695-412e-baae-b4981e54383e
Key points:
• "There’s no direct evidence that Degson connectors are designed to be interoperable with Amphenol SurLok. Users on forums caution against mixing brands due to differences in size, keying, and IP ratings, implying that while Degson might mimic some SurLok functionality, they are not plug-and-play substitutes."
• “Amphenol SurLok is often the benchmark for high-end applications, with Degson sometimes viewed as a "knockoff" or budget-friendly option"