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Stop Trading!: Costco's a Buy

Costco is up after reporting better-than-expected numbers Wednesday. Traders are using the beat to boost retail across the board. That's a "big mistake" as far as Cramer is concerned.

Costco is an "experience," Cramer said today on Stop Trading!. "They made it so you can't regard it as a Wal-Mart or a Target." So Costco can't be used as a measure of the entire retail space, he said.

"Are the other retailers selling gasoline at the lowest price? No, they're not. Do the others have this fresh produce that [Costco has]? No, they don't. This is a single story," Cramer said, adding that he still thinks Costco is a buy.

Also in retail, Gap is up. Cramer credits CEO Glenn Murphy for the fat trimming he did since his arrival. He recommended the stock at its present price of $19 and change.

Oil refiners' margins have "exploded" in the past few weeks, Cramer said, and that's why a number of companies like ConocoPhillips and Valero are up Wednesday despite lowering guidance for the quarter.

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