HPRT MT800 Portable A4 Thermal Printer - Portable and Powerful 

Must be either A4 or letter size, depending on which model you buy, but all paper has to be thermal paper

Nope. This things have lasers that melt the ink

You have to buy cartridges, 20 euros each

Without ink

There is no ink. This unit uses a multi-part process; a thermal transfer ribbon is used in conjunction with the heat of the printer and the other main variable is the need for thermal paper, just like some cash register receipts

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