Radian Audio manufactures a premium 4" compression driver diaphragm, model 1245, for its own model 950 PB compression driver. The Radian model 1245 also fits into several JBL™ 1.4" and 2" exit compression drivers, including model 2445, 2446, 375, 2440, 2441, 2447. 2450, and 2451 model compression drivers. Available in 8 or 16 ohms.