This is the OS Max #871 Muffler for 10 & 15FP, 15LA, 12-15 CZ and CV series engines. It features an adjustable outlet to fit various applications. FEATURES: Aluminum construction Adjustable exhaust outlet on rear of muffler Pressure fitting(installed) INCLUDES: One complete #871 muffler w/pre-installed pressure nipple Four 2.5mm x 24mm screws, for mounting muffler to engine OSMG6882 REQUIRES: Phillips screwdriver for installation SPECS: Overall length: 95.3mm (3.75") center to center of mounting holes: 27.5mm (1.085") rectangular exhaust port: 4.8mm (.192") x 22.2mm (.876") weight: 39.5g (1.4oz) COMMENTS: May fit other .10-.15 size engines that share the same exhaust dimensions as the OS Max engines. For 11.5mm extenstion use OSMG2584 For 90° adapter use OSMG2596 NNA 12/23/01