The Duo is an insertable dildo used for strap-on play between partners, commonly referred to as pegging these days. It is generally worn by the female and used to penetrate a male or another female (anal or vaginally). The end butt is inserted into the vagina and held in place by the PC muscles of the vagina. It can also be used in conjunction with a harness for the increased stability. Preferences vary on this and will depend on the person wearing to decide what works best for them. It also has an insertable bullet vibe that adds extra stimulation for both partners.

This is a perfect toy for a woman who wants to peg her partner and have some sensation or feedback on her thrusting and gain some added pleasure from doing so. Some women might just enjoy parading around with an erect penis.

It can work as a solo dildo too. I think the size works for most levels of experience. Some beginners might prefer less girth, while size queens might want more. I believe that it's an ideal average size.

The material is 100% silicone, which is a 10 on the EF safety scale. It has a smooth matte finish and comes in a natural flesh-like color. It is firm, and does bend, but takes a little bit of force to do so. It is pliable as well but definitely retains its shape and posture well. There is a slight amount of drag, so you might want to be liberal with some water-based lube.

It has no smell or taste. Silicone is also food-grade material, hypoallergenic, latex-free and phthalates-free.

The design is ergonomic and realistic looking with a slightly bulbous head and phallic shape. It also has a vivid bright purple color. It looks great and is nearly a perfect size.

It measures out at 7.5" with just under 6" being insertable. The diameter maxes out at 1 3/8". It has a decent heft.
Not only is the penis head slightly contoured for added anal/prostate/g-spot pleasure, but there are contoured nubs on the vaginal peg and along where the clit rides, so the bumps can give pleasure to the clit as she penetrates her partner. A well thought out design.

The size, look, and firmness of the toy is great. The vibrations are about what you would expect. Decent, but not mind-blowing, but they do transmit through the medium. You can and may prefer using this with a harness, but that will vary from person to person. The vaginal part was smaller than I imagined, which is good if you are petite and tight, but I wonder if all women will have a hard time retaining this inside them? Maybe if you squeeze your thighs, it's easier to maintain insertion. The vaginal knob is also pretty flexible. I'm not sure if that is good or bad, but I expected it to have more firmness. I'm not sure what works best though as I am new to this type of toys.

Because Duo is 100% silicone, care is easy. The usual options apply. Wash it with soap and hot water, soak in 10% bleach solution, use a toy cleaner, or use your dishwasher. Make sure you removed the bullet when you clean it. Store the bullet with batteries removed if you won't be using it for a while. It's recommended to use water-based lubes with Duo. Storage is also typical: in a drawer, in a pouch or a toy box.