An apparatus and system for adjusting transfemoral prostheses by means of an extensible mesh mechanism that has a mechanical internal structure of multiple adaptability and an adaptable modular mesh that allow the adjustment of the apparatus to the amputated section regardless of its shape or size, in addition to having a ventilation module that allows the patient’s support area to be aerated. The purpose of the prosthesis is to make it easy for the user to acquire a prosthesis that is adaptable to the shape and size of its residual limb without the need to replace the device when the characteristics of its amputated limb change, Also to empower the user the ability to move with the prosthesis without inconvenience and to carry out their daily activities in a natural and progressive way with safety, comfort and confidence. The proposed prosthetic innovation seeks to contribute to the improvement of the quality of life of the user who for various reasons has lost part of the lower limb, not only in physical appearance but also that it can progressively resume its daily activities with greater confidence, naturalness in the movement and performance of usual activities, comfort and connection between the prosthesis and the user with a safe adaptation, without complexity and without hurting the residual member and finally that the device is accessible to the user, in cost and functionality.