Wow.... sounded like a good idea but 49.00 for 6 ? My arrows are pricey enough!
They don't seem to buy into FOC much.... so it would be fun to try, but 50 + shipping is an expensive try... wait to hear back from somebody on this site.
Copied and pasted their weight.
Spectrum Standard = 65.5 Grains
*Don’t forget you remove 2.75″ of shaft weight to achieve proper arrow length*
2.75″ @ 9.9 grains / inch = (-) 27.2 grains removed from shaft
Add Back (+14 grains) for the insert (Standard Arrow Insert For Your Shaft)
Spectrum Standard – 2.5″ (shaft weight) + insert = Added Weight
In this example: 65.5 – 27.2 (removed shaft length weight) = 38.3 + 14gr (added insert) = 52.3 grains added.
Spectrum Light = 57.4 Grains
2.75”@ 11.3 grains /inch = 31.1 grains removed from shaft
Add Back (15.

for the HIT insert
In this example: 57.3 – 31.1 (removed shaft length weight) =
26.3 +15gr (added Insert) = 41.2 grains added.