From the announcement (note: all mentions of "this post" refer to Corvus Belli's post. Replying here won't put your name in the hat):
We draw 1 Infinity Cargo Box by Bandua Wargames! Choose yours! To participate, you just need to comment on this Facebook post, or on Twitter using the hashtag #InfinityCargoBox answering the following question: “Wich Infinity Cargo Box do you prefer?” Everyone who post a comment during today, January 31st, will participate in the draw. We'll announce the winner (February 1st) Good luck to everyone!