L2 shows all the Market Makers (MMs)and their depth, their lot size and the price they are buying and selling. If you have a decent amount of money in stocks you shouldn't trade without it. L2 lineups can tell you alot about a stock and what might happen short term. I use AlphaTrade(.com)- $40+ bucks a month. If you want to make money, get it! Been watching L2 for hours each day for 2 years now so I have a fairly good understanding of what's going on with it.
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He who loves money will not be satisfied with money, nor he who loves abundance with its income. This too is vanity.
-Eccl 5:10