A refuelling device for supplying liquefied gases, comprising a feed system adapted to place a plurality of refuelling reservoirs in fluidic through connection with at least one tank; said feed system comprises - withdrawal ducts, each of which is adapted to withdraw said liquefied gas from one of said reservoirs; - an inlet duct for introducing said liquefied gas into said tank; - a collection manifold adapted to convey said liquefied gas from said withdrawal ducts, and therefore from said reservoirs, into said inlet duct; - at least one pump adapted to move said liquefied gas in said feed system, thus allowing said liquefied gas to be simultaneously withdrawn from each of said reservoirs; - for each pump, a pressure gauge adapted to measure the inlet pressure of said liquefied gas entering said pump and a pressure meter adapted to measure the outlet pressure of said liquefied gas exiting said pump; and - a regulating valve for adjusting the flow in said inlet duct according to the difference between said inlet pressure and said outlet pressure; and comprising a pressurization system comprising a connecting member adapted to place the reservoirs in reciprocal fluidic through connection so as to place said reservoirs under the same pressure; and wherein said pressurization system is adapted to place said tank in fluidic through connection with each of said tanks, thus allowing the boil-off of said liquefied gas in said tank to be introduced into each of said reservoirs, thereby raising the pressure of said reservoirs. said feed system comprises - withdrawal ducts, each of which is adapted to withdraw said liquefied gas from one of said reservoirs; - an inlet duct for introducing said liquefied gas into said tank; - a collection manifold adapted to convey said liquefied gas from said withdrawal ducts, and therefore from said reservoirs, into said inlet duct; - at least one pump adapted to move said liquefied gas in said feed system, thus allowing said liquefied gas to be simultaneously withdrawn from each of said reservoirs; - for each pump, a pressure gauge adapted to measure the inlet pressure of said liquefied gas entering said pump and a pressure meter adapted to measure the outlet pressure of said liquefied gas exiting said pump; and - a regulating valve for adjusting the flow in said inlet duct according to the difference between said inlet pressure and said outlet pressure; and comprising a pressurization system comprising a connecting member adapted to place the reservoirs in reciprocal fluidic through connection so as to place said reservoirs under the same pressure; and - withdrawal ducts, each of which is adapted to withdraw said liquefied gas from one of said reservoirs; - an inlet duct for introducing said liquefied gas into said tank; - a collection manifold adapted to convey said liquefied gas from said withdrawal ducts, and therefore from said reservoirs, into said inlet duct; - at least one pump adapted to move said liquefied gas in said feed system, thus allowing said liquefied gas to be simultaneously withdrawn from each of said reservoirs; - for each pump, a pressure gauge adapted to measure the inlet pressure of said liquefied gas entering said pump and a pressure meter adapted to measure the outlet pressure of said liquefied gas exiting said pump; and - a regulating valve for adjusting the flow in said inlet duct according to the difference between said inlet pressure and said outlet pressure; and comprising a pressurization system comprising a connecting member adapted to place the reservoirs in reciprocal fluidic through connection so as to place said reservoirs under the same pressure; and wherein said pressurization system is adapted to place said tank in fluidic through connection with each of said tanks, thus allowing the boil-off of said liquefied gas in said tank to be introduced into each of said reservoirs, thereby raising the pressure of said reservoirs.