auto exhaust gas silencer BL-506 1.make by stainless steel 2.caliber of 28 ... ~ 62mm 3.paper box package auto exhaust gas silencer BL-506Install on the tail pipe of cars, imitate of swallow ... muffer firmly with 10 mm spanner or wrench.Suitable for :BL-501caliber of 28 ~ 62mmBL-507caliber of 28 ~ 62mmBL-502caliber ... know clear diameter of exhaust, can buy this product. BL-506 auto exhaust gas silencer ...