you need to rephrase this OP;
calling it an airdrop when your obligating people to Send 0.001 ETH for 800 tokens is an ICO and not an airdrop,
if the future of this ICO would be based upon the trustworthiness and correctness of this ANN ... you might want to close the curtains and exit stage left!
0.001ETH is optional,if the participants wants to receive USE token instantly,
So this means that if i send 0.001 eth to the contract address, i will recieve 800 Use token in return emmediately

Do you guys planning an ico?

There is no ICO, Its Only Airdrop 70% 0.001Eth is optional, advantage you will receive 800 USE token instantly.If you didnt send 0.001 you will only receive 400 USE Token.