Vacuum Exhaust Mufflers Porous Plastic Mufflers Model No. M-34/30 ANVER Part Number Exact Replacement For P-Series Muffler No. AThread NPT BDiameter in. (mm) CLength in. (mm) Filter Size Microns Weight oz. (g) M-34/30 N750FF 3/4″ 1.53 (38.8) 5.80 (147) 30 0.60 (17.01)