Hollowed out end,reduce the weight of the solenoid without weakening its suction power, increasing the efficiency of the solenoid. With two M2 screw holes Stroke: 5MM Iron core diameter: 5MM/0.19" Iron core length: 24MM/0.94" Body Size : 13 x 15 x 20mm / 0.51" x 0.59" x 0.79".Cable Length : 160MM/6.3" Weight: 22g/0.77oz Resistance: 50ohms Attractive force: more than 70gf Adaptive voltage: DC6V~12V Power on test: DC 6V Current: 0.1A DC 9V Current: 0.17A DC 12V Current: 0.21A 6V can be energised for a long time, but with low force. 12V can be energised for a long time, but not for too long (1-2 minutes is ok) NOTE: When the working voltage is higher, the power and the suction of the electromagnet are greater. But the current will be greater too, which will result to heat. Please determine the use of the voltage according to the working environment. Package Included: 2 x DC 6V~12V 51Ω Solenoid Electromagnet