What gun buddy will I get

Can someone please explain to me wth even is this. I placed silver 3 on this account since it was iron several acts ago, got it all the way up to imm about to hit radiant, (most of my wins were in ascend-imm) and not to mention I instantly double ranked up out of silver as soon as I got placed it. Why on earth is the three silver triangles on the top of my triangle, does that mean I will get the silver gun buddy for this act even though I’m imm 3 about to hit radiant? I also got mix information from online some saying you get what you peaked some saying you get whatever is at the top of your rank triangle, can someone who actually knows please help, thank you.