Connecticut’s U.S. Senators called for stricter gun laws Monday, demanding that gun dealers across the country refuse to sell the hardware before a background check is completed.

U.S. Sens. Richard Blumenthal and Christopher Murphy were two of the lawmakers who signed a letter to three major gun retailers, asking them to close a loophole that allows them to complete a sale before they get a thumbs up on the background check.

Under current federal law, gun sales can proceed without an approved background check, if that check is not completed within three days of an attempted purchase.

According to Blumenthal and Murphy, gun dealers wondering what they would have to do to comply with the legislation should look no further than the largest gun retailer in the country, Wal-Mart. Since 2002, Wal-Mart has required a completed background check in order to approve a gun sale.

“No check, no sale. It’s as simple as that,” Blumenthal said Monday at a Hartford press conference.