Think of it this way Ruffie. You and I could decide that later this week we want to make a VTSI trade at 1.20. We could pick a day with no bids/asks pre or post-market and one of us could offer the shares at 1.20 and the other could buy them at that price. Pre and post market is a dangerous place if you are not sure about what you are doing and don't use limit prices.
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