Hard Rock Bet said it will give away 500,000 Bonus Spins to Michigan players to kick off the Fourth of July holiday week.
The sweepstakes runs from June 29 through July 5 and is limited to Michigan.
According to the promotion, every Michigan player gets a free entry simply by opting in.
At the end of the promotional period, 5,000 winners are selected at random, using a random number generator.
Each of the 5,000 winners receives 100 Bonus Spins.
Hard Rock Bet said each Bonus Spin is valued at $0.10 per spin.
The promotion also says the spins may land on a single slot or be split across two different games.
To participate, players must log in to their Hard Rock Bet account, find the promotion banner, and opt in.
Entries do not carry over from unoptimized play, according to the promotion page, and wagers placed without opting in first will not count.
Hard Rock Bet said the Bonus Spins prizes are scheduled to be awarded by 5 p.m. on Monday, July 6.
It also states that if technical issues arise, there is a 72-hour window to award the prizes.
The operator said any winnings from the Bonus Spins are credited as cash.
The page describes the sweepstakes as separate from Hard Rock Bet’s standard welcome offer for Michigan new players, which includes 500 Bonus Spins on Cash Eruption plus up to $1,000 back on first-day slot play.
Bonus Spins must be used within 7 days of being awarded.
