You can redeem your points and receive a Splatoon 2 in-game gear download code.
This is a set of four in-game gear items. You can receive:
• Gray FA-11 Bomber
• Brown FA-11 Bomber
• Red V-Neck Limited Tee
• Green V-Neck Limited Tee
Over in Europe, Splatoon 2 fans had to buy a Splatoon 2 Splatfest t-shirt to get a code for this content. Here in the states, we just have to cough up 100 Platinum Points. Grab your set of gear here (thanks Kolma and Andreslop24!)