DOP55-157 Echo Vent Assembly No. 131300-56403. This is a quality aftermarket vent that replaces echo part numbers 131300-56403. Fits models GT1100, 2000, 2100,2102,2103, 2400, SRM 1500, 1501, 2100, 2300, 2301, 2400,2500,2501,3000,3800, SRS2100, PE2400, PB1000/1010, 2400, ES 2000, ANd SHR 2100. for 3/16" line, OD 3/8" length 1".