Can You Name These Parts?

Bought a used carbine this week. It came without a rear sight; because the previous owner had lost it after removing it to install an optic. A few other incidental accessories were also missing so I called Hi Point to see about purchasing the missing items.

Wow...I was blown away by the response from the lady at customer service. She told me they couldn't sell the needed parts; but would send them to me under warranty. I own a lot of guns from different manufacturers; but this was the easiest customer service experience I have ever had.

Anyway, I received a package from Hi Point containing the complete rear sight kit, two Hi Point special tools, a user's manual, and a trigger lock kit. Also included in the package were two plastic pieces that I cannot identify. Rather than try to describe these pieces, I will attach a picture. I put a quarter in the picture for scale. I know I will feel like and idiot when someone tell me what they are.