When it comes to dispose ourselves to buy the car seats for our son in the car, you must choose the model that best meets our needs according to age, weight and height of the child or baby that you intend to use. 1 Car seats for infants in their first months of age this kind of car that are made so that the newborn will go almost lying down so that it is easy to fall asleep at any time. We can place these silliatas both in the backseat in the front seats, but in the event we bring him in the passenger seat, we must bear in mind that you should put in position off the front passenger airbag, since it is a grave danger in case of shock. 2 Car seats for children when the baby now exceeds 10 kg of weight, then we can begin to use another type of chairs that are contained in the groups 1,2,y 3. The Group’s Chair that we choose, will depend on the age and weight of the child. These seats are placed in the same directional sense of progress. We can find car seats in Group 1, which will use them children from 9 to 18 kg, group 2 seats are for children more large, with weight comprised between 15 and 25 kg, and finally, chairs of Group 3 car, for the last stage, to children from 22 to 36 kg ISOFIX connectors many models of chairs used come with adapter into the base to be able to anchor Chair to the security system ISOFIX which comes standard in many cars. This system reduces up to 22% the cervical injuries in an accident.