If you already own a harness: measure the O-ring first. Base diameter against ring diameter is the only compatibility question there is, and getting it wrong is the most common ordering mistake in this whole category. Check which spare rings came in the box while you are at it.
If this is a first strap-on setup: go smaller than feels impressive. Five to six inches with a narrow shaft. Nobody has ever regretted starting too small, and plenty of people have a drawer proving the opposite.
If you want it to feel real: dual density. A firm core inside a soft outer layer bends and shifts under pressure the way a single density toy cannot, and the difference is obvious in the hand before it is obvious anywhere else.
If pegging is what this is for: narrow, curved, and read the guide. The first-timer's guide covers size and angle properly, and those are the two things that decide how it goes.
On length: subtract an inch or two. The base sits against the wearer's body, so the usable length is shorter than the box says. Buy on girth, not on the headline number.
On material: silicone for anything going in a harness. Non-porous, genuinely cleanable, and it holds its shape in a ring. Pair it with a water based lube, because silicone lube degrades silicone toys.
On lube generally: more than partnered sex needs. Neither person can feel what the toy is doing through a harness, which is exactly why it runs dry without anyone noticing until it is uncomfortable.
If you just want a dildo: you do not need this page. Everything here works perfectly well in a hand. The dildos and silicone dildos pages are the wider range without the base requirement.
