There seems to be a lot of new hardware for classic computers these days, including MSX hardware. And Brazilian hardware developer Technobytes is one of those companies that makes this new hardware for MSX computers. Technobytes is currently working on a new external Memory Mapper, serving 4MB of extra RAM.
Technobytes , known for their MSX extentions like OPL4-shockwave and MSX-ethernet, says it will manufacture 20 units of, what they describe as "the most desirable product in the MSX gold era", the 4MB Memory Mapper cartridge. This new RAM extension in the form of an external cartridge, called "Memory Max 4", will cost about US$80 and registration will open soon.
Relevant link: http://www.tecnobytes.com.br/2017/03/new-msx-product.html