Abstract: Butterfly valve with a sealing element in elastomeric material with an internal metal reinforcement, made of a substantially tubular outer valve body, with flow pipe connections for fluids at its extremities, in whcih there is a seal in elastomeric material encircling a disc-shaped, internally mobile shutter, equipped with a diametral axis shaft transversal to the valve body axis, protruding out of the same body and bearing the rotation commanding organs, the sealing element being equipped with an inside metal ring, axially extended substantially for the entire length of the same sealing element, and with external sealing reliefs, in correspondence of which there are related seatings in the external body, an ample elastic deformation of the elastomeric material being allowed in the sealed areas, made of a substantially tubular outer valve body, with flow pipe connections for fluids at its extremities, in which there is a seal in elastomeric material encircling a disc-shaped, internally mobile shutter, equippe