Stocks

Stocks originally were a medieval punishment for misdemeanours, consist of placing boards around the ankles and restraining the person. Although popular myth has stocks at ground levels, most remaining stocks have the feet some 12-18 inches (30-45cm) off the ground. There is no explanation for this but it had the effect that unless a bench was provided, the victim had to hug their knees or lie backwards.

This was a temporary punishment although occasionally death occurred when the person in the stocks, unable to move, either succumbed to  extreme cold or heat exhaustion.
Although originally the person had to lie on the ground, many stocks were used with a bench so that the victim could sit upright.A later version restrained both feet and hands, making it impossible to move, even to scratch an itch or swat away flies and it is this that led to the confusion between stocks and pillories.

The first three photographs show variants of stocks and wrists which bind and hold these immobilised, often heads are also immobilised. 

The first photograph shows the BDSM application of the simple medieval stock, where the submissive is reversed, – the original stock having the person facing the stock with hands and feet restrained but in BDSM, the position is reversed so that the submissive has no option but to display herself and cannot defend herself from a molesting by an amorous Master. In the second photograph, the headboard is removable so that the device can be used as simple stocks  or with the headboard in place the sub is sat upright with legs wide apart and with head restrined and hands restrained, thus allowing a molesting of all of the body and also allowing forced plow jobs. The remaining pictures are technically pillories.