My husband likes this cock ring that has a ball sleeve 
It helps him keep his erection, but he also likes the tugging on his balls and the way it feels different when he cums vs when he’s not wearing it - this is his review of it. I agree with @Green_Eyed_Girl about the vibrators! He loves when I use my bullet and clit vibe or our wand on his balls and the underside of his penis during oral 
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