Strap-on dildo

The first part of a strap-on setup is the harness, which connects the dildo to the wearer's body, usually in a position similar to that of a male's genitals.

While these are simple, many people find them uncomfortable[citation needed] because the strap rubs against the anus and other areas, and they sometimes do not hold the dildo very firmly, causing it to sag, flop, twist, or squeak.

This design leaves the genitals and anus uncovered, and attaches the dildo more firmly, giving the wearer more control.

Some are designed to be worn underneath normal clothing for quick use (if done with the dildo in place, either to give the appearance of a penis or to be able to quickly initiate intercourse, this is sometimes called packing), while others take advantage of the additional strength and sturdiness an item of clothing can provide over a few straps, or just to integrate the strap-on into an erotic outfit.

Inexpensive harnesses tend to just have a round hole in the fabric or leather, while more expensive ones will use a steel or rubber ring.

Used primarily by Doc Johnson, Vac-u-lock dildos have a rippled hollow in their base, which fits onto a matching plug on the harness or other toy.

A number of brands have non-compatible clones of the vac-u-lock system, but dildos and accessories for them are virtually unavailable.

Advantages of this design are that it can be used spontaneously, that it provides deep internal thrusting to both partners, and that the lack of harness makes it more comfortable.

Disadvantages are that the eggs do not prevent rotation or droop, leading to a reduced amount of control unless a harness is employed anyway; a requirement for strong muscles; and the practice needed to become familiar with its use.

While special ones meant for use with a harness do exist, a normal double dildo is straight, is rarely at a comfortable angle for intercourse, and jabs into the cervix of a woman using one.

The standard dildo has a non-tapered or slightly tapered shaft, and often has an enlarged head, similar to a penis.

Standard dildos are the most common by a large margin, and are available in virtually any length and width, material, texture, etc.

Dildos designed for g-spot or prostate stimulation often have a sharp upwards curve at the head, or gradual but still strong curvature the entire length.

When used in many sexual positions, the curve causes strong pressure against the g-spot in women or the prostate in men.

When using one of these dildos for the first time, care should be taken at first to make sure it's comfortable for the receiver, as the strong bend can be difficult to insert or control.

Individual bumps or a water droplet texture on the shaft also causes extra stimulation, and often avoids the washboard effect of evenly spaced ripples.

Some dildos modeled to be realistic penises contain very heavy vein textures on the surface, causing a similar effect.

These dildos are often bulky or heavy, and like all other vibrators need a power source (usually batteries in a pack that clips onto the harness or slips into a pocket on it), but can provide additional stimulation for those who desire it.

These dildos tend to greatly limit the possible positions they are used in, as the angle has to be right for both vaginal and anal penetration when thrusting.

Ejaculating dildos contain a squeeze bulb or other reservoir, which when filled with hot water beforehand, allows the wearer to "come" into the receiver at the proper moment.

A relatively new product in this field is dildos with electrodes for erotic electrostimulation, further increasing the range of sensations the receiver can experience.

Hollow dildos are often sold as penis extensions to increase size (length and/or girth), but the most common use is for men with erectile dysfunction.

These are almost always intended for use by people with vulva, as the external vibrator is rarely positioned well nor provides stimulation for a penis.

This way, the main attachment is at a good angle and position for thrusting, while its movement is transmitted directly to the vaginal plug and clitoris of the wearer.

A common type consists of an opening or rubber ring with a cloth or leather back, similar to what might be used to hold the main dildo to the front of the harness, but positioned over the anus, vagina, or ones for both.

A dildo/plug with a wide base is inserted through the ring, then when the harness is put on, the material pulls tight against it, holding it firm.

However, others share these concerns but question whether politics should be brought into the bedroom, while some opposes the notion that strap-on sex is inherently linked to patriarchy.