The Ultra Fit Sleeves are ridged and bumped in some very strategic ways, and slip over a standard 7-inch vibe. This is a classy, time tested combo which works and works and works.
And, as the box copy crows of the sleeves, they "also fits [sic] snugly on your cock for added size and length!" This is indeed true, although this reviewer is a little unsure why - if one were to have this little ensemble on one's night stand - she would waste time with a cock in need of added "size and length."
But I digress. This is a tried-and-true combo, and a must-have staple for any vibe-happy masterbatrix's orgasm-inducing arsenal.