Um, I found several guys are complaining original Macro Lens for HIK B Series in EU market is much higher.

"The original HM-B201-MACRO lens has a bit stiff price tag (100€) "
Here are the link to get the original lens at lower cost:
https://www.aliexpress.com/item/1005007589699455.htmlhttps://www.isecuseshop.com/product/micro-lens-hik-h11-h21/Due to market strategy, even same item, the manufacturer give different name. This made end-users headacle to differentiate and confused to make decision, not only HIK, but also UNI-T.

See the orginal comments from a buyer lol:
"After a long search, I finally found this macro lens. Unfortunately, the Hikmicro thermal imaging cameras for the European and Asian markets seem to have different names, so that customers are confused by the (incomplete) compatibility lists. To clarify: This macro lens not only fits the H11 and H21 and H21 PRO, but also the B10, B20, B20S, B1L, B21L, etc. The article HM-B201 is 100% identical to HM-5201."