Roland Replacement Speaker Diaphragm KC-500, KC-550 Premium SS Audio Diaphragm for Roland KC-500, KC-550, and many others Specs: Voice coil: 1" (25mm), Diameter: 1-3/4" (45mm), Length: 2-7/8" (72mm), Impedance: 8 ohm, DCR: 7 ohm SUPERIOR quality, LARGEST selection, and the BEST prices! For Roland KC550 confirm terminals are side by side and not 180 degrees apart before ordering. Will not fit Roland KC550 models made in China with terminals on opposite sides. To get the BEST quality repair parts, be sure to buy ONLY from SS Audio and Simply Speakers. Thank you!