Gone are the days of an 'one size fits all' branding that translates into 'one size fits most' or 'one size doesn't fit many women at all' because with the Theo, 'one size' means it accommodates to fit women with anywhere from a 20" to 50" hip measurement. With such a varying range in sizing, this harness covers the sizing gaps while leaving very little gaps between you and it.

In fact, with its single-strap fit, the Theo makes an ordinary dildo feel like a "natural extension of your body, with no gaps, no chafing buckles, and no pinched skin."

With the liberal sizing options and the perfect construction allowing toys and accessories feel like a part of you, this harness is suitable for all day wear including use in a shower or pool; the Theo sets the standard for what a good harness should be.

The Theo is made with multiple layers of Poly-Spandex. Not only is this particular material blend stretchy which allows it to conform to your body, but it's silky and offers a high gloss shine that translates into a harness that is functional and beyond beautiful.

Lined with soft mesh (much like the lining found in a bathing suit) the Theo provides breath-ability for comfortable all-day wear. This vegan-friendly fabric has major appeal for packers because not only is this panty style harness appropriate and desirable for all-day wear but it offers an unique, stretchable, sewn-in elastic o-ring that fits a variety of toys, including your favorite cock! The fact the o-ring is part of the harness material prevents metal o-rings from pinching skin during wear or pinching fingers while trying to equip your cock.

Unfortunately, due to the multiple layers of fabric it is fairly thick so it might not work well under underwear but due to its ability to breathe, you might want to forgo the idea of underwear entirely.

The Theo is a g-string style harness designed to be stepped into. The harness lacks loops or closures on the hip portion so that means that there is no potential for chaffing or discomfort due to hardware rubbing against your very sensitive bare skin.

The 2" wide hip/waistband stretches to fit and is tightened via strong velcro. Atop this thick band are sliders on both sides of the harness that can be tightened to ensure a snugger fit for women with a smaller hip sizing. Underneath the velcro waistband is a soft, smooth backing that makes this comfortable, allowing the potential for extended, all-day and all-night wear.

The crotch area of the harness offers 5 sets of snaps allowing you to customize whether or not you want the harness to sit low or high on your mons pubis. These snaps can be tricky to undo and while buyers may be annoyed with how tricky they are to open and snap close, there is little to no chance that they will pop open during wear and use.

On the underside of the harness is a pouch that opens up to put your dildo through. This pouch allows you to not feel the backing of your chosen toy/attachment which puts it above many other harnesses on the market. I've encountered many dildos that had unfinished edges on the bottom and this pouch prevented me from feeling any of them. While the pouch helps to prevent discomfort it also opens up to allow for the use of double ended dildos. And thanks to the crotch snaps, you can adjust how high/low it sits against your pubic area, which means you can perfectly position the harness to allow the double ended dildo to please both your partner and yourself.

Atop the beautiful Pony-Spandex are eye-catching pearlescent accents which help to give this harness a feminine and expensive feel. Beyond the glamorous adornments, the Theo offers a condom slot in the back which makes safe sex all the more viable when you're out and about.

One of the crowning achievements of the Theo is that it includes a sewn-in o-ring (that stretches to fit varying sized dildos) as opposed to a harness that has metal o-rings that are meant to be changed out for various sized toys. I love the design of this o-ring rather than metal ones because I've had sharp edges on metal o-rings catch on silicone and tear it, the fact the Theo's o-ring is made out of fabric means all my dildos are safe from any nicks or cuts.

SpareParts promises the Theo is "ethically made by hand in the U.S" and comes with the "SpareParts HardWear quality guarantee." It is made beautifully and is structurally sound ensuring unadulterated fun, which means no more stopping to adjust this or that!

The joy of the Theo is it not limited to a specific size range. No, the Theo expands to fit your body and accommodates all shapes up to a 50" waist! Whether you're full bodied or slim, it fits as comfortably like your favorite pair of underwear.

Size A accommodates: 20" to 50” hip sizes and Size B (which can be found here under Theo Harness Large) accommodates: 35" to 65" inch hips.

(As this section is performance based I have to interject my personal experience.)

With all the hype, ranting, and glorification of the customizable sizing of the Theo, the point that remains to be proven is whether or not this is viable to not just wear but USE.

The O-ring is made out of elastic and fabric so it was designed to stretch to fit a range of dildos. Inserting a cock can involve a little bit of difficulty as it's not just "slip in and go", inserting a dildo requires working the elastic o-ring down the shaft of the dildo which can take some time if you're using something with a fairly large diameter. I love my Lone Star dildo (my partner does not for obvious reasons... the fact it has a 5 3/4" circumference) and it took some manipulation of the fabric, a lot of wiggling, and some tugging but the o-ring eventually stretched to accommodate this very thick dildo. Inserting the Throb dildo was a lot easier as it only has a 4" circumference. The Theo held both dildos strongly even with their varying diameters! They did not slip, nor did they adjust themselves against my wishes.

Wearing the Theo is like wearing your favorite pair of underwear. The material is comfortable, it breathes, and the varying sizing options means you get a great fit. It was like a second skin, the harness never sagged, never stretched out, and never gave me a reason to readjust it or take it off. It was a little bulky under my clothes, especially due to the pink slider (that went over the tightened straps to prevent loose ends from getting in the way) that poked out on my hip, but this was a small sacrifice due to the fact it performed beautifully.

If there was ever a harness designed for marathon wear, the Theo's it. Thrusting was easy as dildos never felt like dildos, never made me aware that I was using a toy, and never made me feel inadequate or awkward. The fantasy kept going, I was never once brought to reality due to a slipping toy or a slipping harness, the Theo stayed where I secured it and I was able to work each different toy as if it was a part of my own body.

As the Theo can be used in water, it can also be hand or machine washed making it sanitary and hygienic for repeated use. Spareparts recommends washing your new harness with detergent prior to use as the dye can bleed onto attachments and clothing.

Unfortunately, the Theo cannot be used with oil or petroleum based lubricants as they will stain the fabric.

The Theo comes packaged in a satin drawstring pouch, this pouch is fairly small as it greatly compacts your harness so it can be kept in any sock drawer or on any nightstand but avoid stashing it in a toy box as it will not fair well with oil based lubes.

I absolutely hate the logo right on the front of the harness - I guess with a product so good the company needs to blatantly stamp their trademark on it. Unfortunately, this huge nameplate detracts from the overall beauty and appeal of this harness, and makes it feel a lot more sporty than it should.