Amazon.co.jp: Clarion SRT1733 6.7-inch Multi-Axial 3-Way Speaker。Clarion Speaker SRT-1733 With Tweeter 3 Way 6。Clarion 8。Clarion SRQ1732R 6-3/4。。Features a 16cm diameter multi-axial 3-way structure for balanced sound reproduction from clear highs to mid-lows, designed for automotive use.