If you love the Xcalibur One Knocker, this is an excellent replacement lure for you, since the old Xcaliburs are discontinued and are commanding a pretty steep price.  My understanding is that Booyah bought this out from Xcalibur and uses the same lure molds so it is a pretty close match. 
The Booyah One Knockers have a super-loud deep natural sound that absolutely triggers the predators and can be run at a slower speed than most similar sized lipless cranks for a different presentation when this is called for, such as in the pre-spawn period.
Visually identical lures to the Excaliburs and pretty close in sound and action.  I have selected color patterns that I love.  I've migrated to these for most situations because I'm an absolute believer in the One Knocker concept but I hate to lose my original Excaliburs to the pike and musky in my local waters.  I keep the Excaliburs for tournaments only. I've made these available in 10 different colors and three different weights (3/4 oz, 1/2 oz, and 1/4 oz).  I use the 3/4 ounce size the vast majority of the time because of its big fish triggering qualities, but the 1/2 and 1/4 ounce sizes can be highly productive at times.  I've come to really rely on the yellow perch pattern because they are a predominant baitfish species in my local waters.  Try it out.  I think you'll be impressed.
Best of luck on the water to you!  
Ande

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