Anderson SB50 is actually a concept of safe types of DC connectors which them can be frequently connected and disconnected with out damage.
American companies as for example APC them stated to use this Anderson SB50 connector at their UPS systems in order a single or several battery packs to be connected to them.
Today it seems to me that Anderson SB50 patent this expired, and a new company in Taiwan added this design in their product line too.
From the pictures I cannot say if these products made by K.S.TERMINALS INC, them are 100% compatible to mate with an Anderson SB50.
https://www.ksterminals.com.tw/eng_index.asphttp://edm.ksterminals.com/uploadfiles/131/edm/Battery_Modular_Connectors/10/