JIAJIN-0528S ultrasonic spot welding machine 28khz 500W 8kg 250*250*150 mm 220-240V/2A JIAJIN-ULTRASONIC HANDHOLD WELDING MACHINEWITH THE FOLLOWING FEATURES : 1,Small in size ,easy work , not accoutnting for apace2,The ultrasonic frequency is 28 khz3,Transducer chip improted Japan4, Auto-recovery frequency easy to adjust.5,Original Japan NTK vibrator ,stable output6,Handset transducer,easy to ...