The FMF Q4 Hex S/A Slip-On Exhaust Muffler, manufacturer part number 045590 and vendor part number 79-4193, is designed for select KTM and Husqvarna motocross and off-road motorcycles. This performance muffler uses internal baffles, chambers, and advanced sound-absorbing materials to improve exhaust flow while maintaining controlled sound output and minimizing power loss. Its slip-on design provides a practical upgrade for riders seeking dependable performance and trail-ready sound management.
With sound output typically well below 96 dB on compatible machines, the FMF Q4 Hex helps meet strict noise requirements in many riding environments. The integrated U.S. Forestry-approved spark arrestor uses a maintenance-free stainless steel screen to support responsible off-road riding and reduce the risk of expelled sparks. The durable construction is suited to the demands of motocross, cross-country, and recreational trail use.
This FMF exhaust muffler fits the 2015 KTM 250 SX-F Factory Edition, 2015 KTM 450 SX-F Factory Edition, 2016-2017 KTM 350 XC-F, 2016-2017 KTM 350 SX-F, 2016-2017 Husqvarna FC 250, and 2016-2017 Husqvarna FC 450. Verify the motorcycle model, year, exhaust configuration, and mounting points before installation to ensure proper fitment. The Q4 Hex S/A Slip-On is intended as a model-specific replacement or performance upgrade for compatible applications.
Features:
- Performance Design: Internal baffles, chambers, and sound-absorbing materials help accelerate exhaust flow with reduced noise and minimal power loss.
- Sound Control: Typically operates well below 96 dB on most compatible machines to help satisfy strict sound requirements.
- Spark Arrestor: U.S. Forestry-approved spark arrestor with a maintenance-free stainless steel screen supports responsible off-road use.
- Fitment: Fits select 2015-2017 KTM and Husqvarna models, including KTM 250 SX-F Factory Edition, KTM 450 SX-F Factory Edition, KTM 350 XC-F, KTM 350 SX-F, Husqvarna FC 250, and Husqvarna FC 450.
- Identification: FMF brand, Q4 Hex S/A Slip-On model, manufacturer part number 045590, and vendor part number 79-4193.
Fitment:
2015 KTM 250 SX-F
2015 KTM 250 SX-F Factory Edition
2015 KTM 350 SX-F
2015 KTM 450 SX-F
2015 KTM 450 SX-F Factory Edition
2016 Husqvarna FC 250
2016 Husqvarna FC 350
2016 Husqvarna FC 450
2016 KTM 250 SX-F
2016 KTM 250 XC-F
2016 KTM 350 SX-F
2016 KTM 350 XC-F
2016 KTM 450 SX-F
2016 KTM 450 XC-F
2017 Husqvarna FC 250
2017 Husqvarna FC 350
2017 Husqvarna FC 450
2017 Husqvarna FE 250
2017 Husqvarna FE 350
2017 Husqvarna FE 450
2017 Husqvarna FE 501
2017 Husqvarna FX 350
2017 Husqvarna FX 450
2017 KTM 250 EXC-F
2017 KTM 250 SX-F
2017 KTM 250 XC-F
2017 KTM 350 EXC-F
2017 KTM 350 SX-F
2017 KTM 350 XC-F
2017 KTM 450 EXC-F
2017 KTM 450 SX-F
2017 KTM 450 XC-F
2017 KTM 500 EXC-F
2018 Husqvarna FC 250
2018 Husqvarna FC 350
2018 Husqvarna FC 450
2018 Husqvarna FE 250
2018 Husqvarna FE 350
2018 Husqvarna FE 450
2018 Husqvarna FE 501
2018 Husqvarna FX 350
2018 Husqvarna FX 450
2018 KTM 250 EXC-F
2018 KTM 250 SX-F
2018 KTM 250 XC-F
2018 KTM 350 EXC-F
2018 KTM 350 SX-F
2018 KTM 350 XC-F
2018 KTM 450 EXC-F
2018 KTM 450 SX-F
2018 KTM 450 XC-F
2018 KTM 500 EXC-F
2019 Husqvarna FE 250
2019 Husqvarna FE 350
2019 Husqvarna FE 450
2019 Husqvarna FE 501
2019 KTM 250 EXC-F
2019 KTM 350 EXC-F
2019 KTM 450 EXC-F
2019 KTM 500 EXC-F