NEW OLD STOCK ONE PAIR OF MARTIN ARCHERY SPEED DEMONS. PACKAGE SAYS: USED TO DAMPEN OSCILLATIONS OF THE BOWSTRING RESULTING IN MORE ENERGY BEING TRANSMITTED TO THE ARROW. PRODUCT GIVES AN AVERAGE OF 5-7 FEET PER SECOND. WHEN PROPERLY INSTALLED AND ADJUSTED THE BOW WILL SHOOT THE MOST ACCURATELY. INSTALLATION INSTRUCTIONS AND ADJUSTMENT INSTRUCTION INCLUDED.
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