A system for delivering tumor treating fields, TTFields, to a body of a subject, the system comprising: an electric field generator configured to generate an electrical signal having an alternating current waveform at a frequency in a range from 50 kHz to 500 kHz; a first conductive lead (58; 58a) electrically coupled to the electric field generator , the first conductive lead (58; 58a) being configured to carry the electrical signal; a first pad (70; 70a; 70c; 70d; 70e) coupled to the first conductive lead (58; 58a), the first pad (70; 70a; 70c; 70d; 70e) having a foam and a first conductive gel element ; a second conductive lead (58; 58b) electrically coupled to the electric field generator , the second conductive lead (58; 58b) being configured to carry the electrical signal; and a second pad (70; 70b; 70c; 70d; 70e) coupled to the second conductive lead (58; 58b), the second pad (70; 70b; 70c; 70d; 70e) having an electrode element (104; 136) and receiving the electrical signal from the second conductive lead (58; 58b), the electrode element (104; 136) being connected to a second conductive gel element ; characterised by : the foam being a conductive foam and receiving the electrical signal from the first conductive lead (58; 58a); the conductive foam having a solid continuous phase material being at least one of constructed of a conductive material or having a conductive material attached, absorbed or adsorbed to the solid continuous phase material and defining a plurality of pockets (240; 240a-d) interspersed throughout the solid continuous phase material ; and the first conductive gel element being attached, absorbed or adsorbed to the conductive foam . an electric field generator configured to generate an electrical signal having an alternating current waveform at a frequency in a range from 50 kHz to 500 kHz; a first conductive lead (58; 58a) electrically coupled to the electric field generator , the first conductive lead (58; 58a) being configured to carry the electrical signal; a first pad (70; 70a; 70c; 70d; 70e) coupled to the first conductive lead (58; 58a), the first pad (70; 70a; 70c; 70d; 70e) having a foam and a first conductive gel element ; a second conductive lead (58; 58b) electrically coupled to the electric field generator , the second conductive lead (58; 58b) being configured to carry the electrical signal; and a second pad (70; 70b; 70c; 70d; 70e) coupled to the second conductive lead (58; 58b), the second pad (70; 70b; 70c; 70d; 70e) having an electrode element (104; 136) and receiving the electrical signal from the second conductive lead (58; 58b), the electrode element (104; 136) being connected to a second conductive gel element ; characterised by : the foam being a conductive foam and receiving the electrical signal from the first conductive lead (58; 58a); the conductive foam having a solid continuous phase material being at least one of constructed of a conductive material or having a conductive material attached, absorbed or adsorbed to the solid continuous phase material and defining a plurality of pockets (240; 240a-d) interspersed throughout the solid continuous phase material ; and the first conductive gel element being attached, absorbed or adsorbed to the conductive foam . the foam being a conductive foam and receiving the electrical signal from the first conductive lead (58; 58a); the conductive foam having a solid continuous phase material being at least one of constructed of a conductive material or having a conductive material attached, absorbed or adsorbed to the solid continuous phase material and defining a plurality of pockets (240; 240a-d) interspersed throughout the solid continuous phase material ; and the first conductive gel element being attached, absorbed or adsorbed to the conductive foam . <EOS>