Hello. On the product photos on the site on the transformer LITE TDA1543 X8 on top of the sticker R-26-3. after receiving the duck and opening it, I saw on the transformer LITE TDA1543 X8 a sticker R-26 on top and an SR-25 stamp on the side face. Which transformer actually costs, which one is better, what is the difference between R and SR and why is there such a discrepancy in the description of the product and the installed components? thank.