Areal Lumenock adds 22 grains.So arrow with a easton nock at 350 grains would now weigh 372 grains with Lumenock.
So now...when you subtract the weight of your standard arrow nock you get what difference??????
I can tell you from my limited experience......of maybe shooting 40 shots with mine ......beside hundreds of shots with my other hunting arrows NOT equipped with the lumenoks.....(out of my Mathews Switchback @ 64# and my Bowtech Allegiance @ 71#).....it makes NO DIFFERENCE.
I also have NEVER had one fail to illuminate.
That's my experience with the product.