Part Number :99944200907 99944200902,Fit for most ECHO SRM straight shaft trimmers. Such as SRM210 SRM225 SRM200 SRM230 SRM250 SRM265 SRM266 SRM280 SRM2100 SRM2400 and so on. Universal Speed Feed Trimmer Head: Fits most premium trimmer brands including Echo, Honda, Husqvarna, Maruyama, RedMax, Shindaiwa, Stihl. Fits Echo PAS Series Trimmers: PAS210, PAS211, PAS225, PAS225VP, PAS225VPB, PAS230, PAS231, PAS260, PAS261, PAS265, PAS266, PAS280, PAS2100, PAS2400, PAS2601 Fits for Shindaiwa Trimmer Head: replace 78890-30000,78890-11000, 78890-18001,78890-18000.22T, C230, C242, C2510, T195s, T220, T222,T230, T231, T230s, T242, C242, T242X, T2510, C2510, T2510X, BP35, B45, B450, C350, T235, T344, C344, T254, C254, F18, F20, F21, F22, F230, F195 Size:Speed feed 400 Trimmer Head Diameter is 3-3/4 inch,Uses .080", .095" Diameter Line;Adapter Size:10mm x 1.25mm LHF ; TIPS: Doesn`t Come With Adapter.Only for Straight Shaft Model Trimmers. Not Fits Curved Shaft Trimmers! Please confirm your engine's model and part numbers before purchasing. YOBFO universal speed feed trimmer head fits most premium trimmer brands including Echo, Honda, Husqvarna, Maruyama, RedMax, Shindaiwa, Stihl. Perfect for ECHO straight shaft SRM model trimmers! Our weed eater head also fits PAS models with the straight shaft trimmer attachment. It will NOT fit PAS models with the curved shaft attachment. INCLUDING BUT NOT LIMITED TO: SRM-140SRM-200SRM-202SRM-210SRM-220SRM-225SRM-225iSRM-225USRM-230SRM-250SRM-251SRM-260SRM-261SRM-265SRM-266SRM-280SRM-300SRM-302SRM-303SRM-311SRM-330SRM-340SRM-343SRM-350SRM-400SRM-402SRM-500SRM-501SRM-1500SRM-1501SRM-2010SRM-2090SRM-2100SRM-2110SRM-2200SRM-2201SRM-2300SRM-2301SRM-2400SRM-2410SRM-2450SRM-2500SRM-2501SRM-2502SRM-2510SRM-2530SRM-2601SRM-3000SRM-3001SRM-3010SRM-3100SRM-3110SRM-3400SRM-3410SRM-3500SRM-3550SRM-3800SRM-4600. Speed Feed 400 Trimmer Head Part Number:99944200907. Trimmer Head Diameter is 3-3/4 inch,Uses .080", .095" Diameter Line;Adapter Size:10mm x 1.25mm LHF ;. Package Included:Universal Speed Feed Trimmer Head*1Pack