Psa 18" chf mid-length 5.56 nato 1:7 heavy 15" precision lightweight m-lok upper, no bcg or ch - 516444448

[Mk262Mod1]

I have a question about the PSA 18" upper with the heavy FN CHF barrel, part # 516444448:

there are two holes in the forearm, in the area over the barrel nut, at the 9:00 and 3:00 positions. What are they for? Are they QD mount receptacles? The official product description doesn’t say anything about them and there are no instructions that come with the upper, so I thought I’d ask. Thanks.

Link to product

[GuitarGuy]

Yes.

[Mk262Mod1]

Thank you!