Sort:  

You give them SBD and based on the total they receive from everyone in that voting period, they upvote your post with a percentage of their voting power. The links are to a calculator to help you decide how much SBD to send.

They are also asking for delegation of SP to them as an investment. As with any of these types of things here, your results may vary.

Coin Marketplace

STEEM 0.19
TRX 0.15
JST 0.029
BTC 63811.50
ETH 2617.28
USDT 1.00
SBD 2.77