From the perspective of increasing the height of shoe brand promotion in the market, the mainstream height is 5 to 13 cm, and the best height is about 7 cm in terms of wearing comfort and invisible effect. The heightening layer is also known as the inner heightening insole. The two main heightening layers used in heightening shoe products on the market are the semi-cushioned heightening layer and the full-cushioned heightening layer.

The heightening principle of the concealed inner heightening shoes is to make the inner heightening pad of special pressure-resistant and breathable materials and put it in the specially designed shoes to achieve the heightening effect. Similar to women's high-heeled shoes, but the design structure is much more comfortable than women's high-heeled shoes, and there is no discomfort after wearing them. The appearance of the concealed inner heightening shoes is the same as that of ordinary high-grade leather shoes, which not only makes people not see the secret of heightening, but also makes people feel comfortable.