Hip and buttock padding is used by some transgender

Transgender

Transgender is a general term applied to a variety of individuals, behaviors, and groups involving tendencies to vary from culturally conventional gender roles....

 people including transsexuals and cross-dressers. It is used to increase the apparent size of the hips

Hip (anatomy)

In vertebrate anatomy, hip refer to either an anatomical region or a joint.The hip region is located lateral to the gluteal region , inferior to the iliac crest, and overlying the greater trochanter of the femur, or "thigh bone"...

 and buttocks

Buttocks

The buttocks are two rounded portions of the anatomy, located on the posterior of the pelvic region of apes and humans, and many other bipeds or quadrupeds, and comprise a layer of fat superimposed on the gluteus maximus and gluteus medius muscles. Physiologically, the buttocks enable weight to...

 to resemble those of a female. The padding is intended to improve the person's chance of passing

Passing (gender)

Passing refers to a person's ability to be regarded as a member of the sex or gender with which they physically present. Typically, passing involves a mixture of physical gender cues as well as certain behavioral attributes that tend to be culturally associated with a particular gender...

 as female by altering their apparent waist-hip ratio and shoulder-hip ratio.

Pre-made

Padded underwear with pockets into which sections of padding can be inserted are marketed by companies catering to crossdressers. Many of these premade garments are often criticised for looking lumpy or false.

Made to measure

At least one company specialises in manufacturing custom made garments specifically designed from the purchaser's measurements. These garments are more expensive than pre-made or home made garments but are generally well made.

Homemade

The cheapest form of hip and buttock padding is homemade. Information on making padding is available on web sites and in at least one book.

Using the person's own measurements and a table of comparative measurements, it is possible to determine how thick the padding needs to be at various places, such as the widest point on the hips and the fullest point on the buttocks.

Homemade padding is usually made by cutting a block of high-density polyurethane foam rubber

Polyurethane

A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...

 to shape. This is the same type of foam as used for upholstery

Upholstery

Upholstery is the work of providing furniture, especially seats, with padding, springs, webbing, and fabric or leather covers. The word upholstery comes from the Middle English word upholder, which referred to a tradesman who held up his goods. The term is equally applicable to domestic,...

. The most common tool used for shaping the foam is an electric knife

Electric knife

An electric knife or electric carving knife is an electrical kitchen device used for slicing foods. An electric knife requires less physical effort than an ordinary knife and produces neater slices. The device consists of two serrated blades that are clipped together...

. The block is usually cut as a flat piece which is wrapped around the hips and buttocks, rather than being carved as a curved piece. The foam is carved only on the inside, so that the outside surface remains smooth.

The padding is usually worn inside a compression garment such as one intended to be worn by females to lift and shape the buttocks.