Strap-Ons & Harnesses

A strap-on dildo is one made to be worn in a harness rather than held: a flat, wide base that sits against the body, a shaft that stands at the right angle, and a size that the partner on the receiving end can take comfortably for as long as the two of you want. The dildo and the harness are chosen together; a good dildo in the wrong harness flops, and a good harness with the wrong dildo hurts. This guide covers both, from the dildo's side.

The base decides the fit

A harness holds the dildo by its base, through an O ring or a Vac-U-Lock plug. For an O ring, the base needs to be flat, wide and firm, a good deal wider than the ring, so it cannot pull through; a base of six to eight centimetres suits most rings. Vac-U-Lock dildos have a hole in the base that fits a ridged plug on the harness, hold rock steady, and only work with that system. A dildo with a suction cup works in an O ring too, and the cup keeps it from turning.

Angle, and why a slight curve helps

A shaft with a gentle upward curve points where the front wall or the prostate is, and follows the wearer's hips rather than fighting them. A straight shaft suits positions from behind. Too much curve is harder to aim from a harness than by hand, so save the strongly hooked shapes for handheld use.

Size

Choose for the partner who receives, and smaller than you think for a first: around 14 to 16 centimetres insertable and a girth under 13 centimetres is a comfortable place to start for vaginal use, and smaller again for anal. Length that will not be used just makes aiming harder. A wearer who is new to thrusting does better with a slightly shorter shaft, because control comes from the hips and shorter is easier to control.

Firmness

A dildo in a harness needs enough firmness to stay up: very soft silicone folds under its own weight and bends away on entry. Medium or firm silicone, or dual density with a firm core, is the right choice. If the same shape comes in several firmnesses, take the firmer one for harness use.

Double ended and wearer's side

Double dildos for harness use have a short bulb that sits inside the wearer, held by the harness, so both partners are penetrated. They need a harness with a ring that leaves room for the inner end, and the inner bulb must be sized for the wearer. Some dildos carry a vibrating bullet in the base that both people feel.

Material

Platinum silicone, as always for anything that goes inside the body. It is also the only material with a range of firmness, which matters here. Avoid jelly and PVC strap-on kits, however cheap; they are porous, they sag, and they are usually paired with a harness that does not last either.

Harness basics

A harness with a ring that can be swapped fits more dildos; four points of adjustment hold a heavy dildo better than two. Leather and neoprene are the durable materials; briefs style harnesses are comfortable and quick, and suit lighter dildos. The dildo and the ring must match: a ring too small will not take the base, a ring too big lets the dildo tilt.

Care

Wash with warm water and soap after every use; solid silicone can be boiled. Water based lubricant only. Store the dildo apart from the harness; leather and silicone kept pressed together for months can mark each other.

Frequently asked questions