The shrink tube is probably the covering over the speed balls (2 brass nock sets near the cam). It's not necessary. Just carefully cut it off.
Don't know how much speed you'd lose with Bow Jacks. I'd just use some Simms string silencers, being as I can get them for free. I forget what they're called. Brain fart.
I haven't looked at any pics of Cheetahs lately, but the reason they have Bow Jacks and yours doesn't is because yours has the STS and the Cheetah doesn't. Tit for tat.
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