In the market for sous vide cookers, there are two main types of machines: portable clip-on digital circulator (with shaker) and water baths (without a shaker).
In the first case, we have the portable devices that are attached to any container that meets minimum requirements in terms of capacity and depth. Being portable, it is easy to transport and take up very little storage space. These boilers are equipped with a shaker that moves the water at all times, ensuring uniform temperature throughout the cooking container.
Water baths are containers with a fixed capacity and resistance over its entire surface, so that a uniform cooking can be done. By having a fixed capacity, they are not as versatile as portable models. They tend to occupy a fixed space in the kitchen, since their volume is not easy to store. The advantage of these devices is their self-sufficiency, in the sense that they do not need any external container for its use.
Sammic provides a portable model with shaker that can be complemented with containers and lids, as well as several models of water baths that vary in size.