About the only thing on a lake's bottom that never gets tired of biting is the bottom itself. Particularly with moving "reaction" lures like crankbaits, snags are practically an assumption. Crankbaits attract fish because they cover water quickly to find those reaction strikes, but this swift motion leaves little time to avoid the entanglement of running headlong into brush, logs or rocky crevices.

Most agree that if you don't occasionally snag something, you're not fishing where the fish are, but that's little solace when you risk losing your favorite lure. Tugging offers little more than a frustration vent — one that usually worsens matters by driving hooks deeper or wedging an entire lure tighter into whatever vexation grips it. "Snapping" the snag — pulling a taut line to the side and releasing it to snap a loosening tremor down to the point of ensnarement — may work for instances of moderate snags.

But when your bait stumbles into serious captivity, it's time to send in the repo man of fishing — the lure knocker.

In simplest terms, this tool comprises a weighted form that attaches to your main line and slides down to "knock" the snagged lure free. As most snags occur while lures are moving forward, lure knockers strike their target front-to-back with a motion intended to push the bait away from its entrapment.

Commercially marketed lure knockers vary in size, weight and design based on the depth and cover for which they're intended. Examples range from the rocket-shaped Strike Zone Lure Co.'s Pocket Knocker Lure Retriever to the EZ Lure Retriever comprising a heavy lead weight — shaped and painted to resemble a baitfish — with an open-ended metal frame extending from its back, a retrieval cord attached to its tail and chains dangling from the head.

When a snag occurs, slip the metal frame over your line, hold the retrieval cord in one hand with the fishing line in the other and let the lure knocker slide down to the snag. If the initial impact doesn't do the trick, raise and drop the knocker in short, sharp bumps until you feel the fishing line come free. For particularly stubborn snags, those dangling chains can be manipulated to grab hooks and pull the bait loose.