The Tier 4 Present was added to Pet Simulator in Update 7
This present costs 4,100,000,000 coins, as of Update 7.
Inside the present you will find the following hats:
Rarities[]
Common: Hatstack, Noob Sign
Uncommon: Rubber Duckie, Blue Top Hat
Rare: Neon Pink Banded Top Hat
Legendary: Bling Top Hat
Mythical: Robux (Hat)