Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 10 - Jul 15
Promo Codes Available:
For Your Every Summer RSVP, with Code: SUMMER15
Description
Flowmonster Performance Muffler 3 in Dual inlet & outlet 12599-FM 409 StainlessOverview The Flowmonster series of absorption style mufflers deliver a moderate tone for the enthusiast looking for a deeper, more aggressive exhaust note than most OE (Original Equipment) mufflers, unlike the racey exhaust note associated with "chambered" style mufflers. Interior construction features 3. 50 inch "straight through" perforated 409 stainless steel tube surrounded by high temperature sound absorption packing material which helps to
Overview
The Flowmonster series of absorption style mufflers deliver a moderate tone for the enthusiast looking for a deeper, more aggressive exhaust note than most OE (Original Equipment) mufflers, unlike the racey exhaust note associated with "chambered" style mufflers.
Interior construction features 3.50 inch "straight-through" perforated 409 stainless steel tube surrounded by high-temperature sound absorption packing material which helps to deliver a deeper, mellower exhaust note. The internal design is reversible allowing the flexibility to be installed in either direction to best accommodate fitment with the intended vehicle. The fully MIG-welded 409 Stainless Steel material is embossed with the "FLOWMONSTER" logo on the case.
Interior construction features 3.50 inch "straight-through" perforated 409 stainless steel tube surrounded by high-temperature sound absorption packing material which helps to deliver a deeper, mellower exhaust note. The internal design is reversible allowing the flexibility to be installed in either direction to best accommodate fitment with the intended vehicle. The fully MIG-welded 409 Stainless Steel material is embossed with the "FLOWMONSTER" logo on the case.
Features:
- 409 Stainless Steel construction for superior corrosion resistance and good looks
- Interior construction features high-temp interior sound absorption material delivering a deeper, mellow exhaust tone
- Perforated High-Flow straight-through tube design for increased exhaust flow
- Moderate increase in interior tone over most OE mufflers
- A stainless steel performance muffler at an economical price
- Internal Design is reversible allowing flexibility to be installed in either direction
- Sold Individually
- This is a Universal Fit muffler - Not a Direct fit. Some adaption may be required for proper fitment on some applications
| Body Height (in) | 5 |
| Body Length (in) | 22 |
| Body Width (in) | 11 |
| Finish | Natural |
| Fitment | Universal |
| Inlet Connection Type | Pipe Connection |
| Inlet Inner Diameter (in) | 3 |
| Inlet Outer Diameter (in) | 3.13 |
| Inlet Position | Dual |
| Material | 409 Stainless Steel |
| Muffler Series | Flowmonster |
| Muffler Type | Absorption / Glasspack |
| Outlet Connection Type | Pipe Connection |
| Outlet Inner Diameter (in) | 3 |
| Outlet Outer Diameter (in) | 3.13 |
| Outlet Position | Dual |
| Overall Length (in) | 28 |
| Reversible | Yes |
| Shape | Oval |
| Sound Level | Moderate Sound |
| Type of Muffler | Absorption |
| Part Number | 12599-FM |
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.8 ★★★★★
Based on 2489 reviews
Sort
Product Reviews
★★★★★ 5
Good quality
Color: 4 Panels Natural, Size: 4 Panels
Nice quality. Used for a wedding table assignment. Looked lovely!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 9, 2026
★★★★★ 5
Nice Looking Scree, Good Quality Rattan
Color: 6 Panels Black, Size: 6 Panels
Very attractive screen and much better rattan quality than expected. Would definitely recommend this product.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 30, 2026
★★★★★ 3
Looks great but not that sturdy
Color: 6 Panels Black, Size: 6 Panels
These are very nice they look really pretty. The only thing is they seem a bit flounder than they look online. I definitely feel like you have to be careful with somebody they don’t break.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 15, 2026
★★★★★ 5
Great for the price
Color: 4 Panels Natural, Size: 4 Panels
Great for the price. A little flimsy, but better than I expected at this price
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 17, 2026
★★★★★ 1
Arrived damaged
Color: 6 Panels Natural, Size: 6 Panels, Color: 6 Panels Natural, Size: 6 Panels
Arrived with hole in the panel.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 30, 2026
recommand products
White Floral Designer iPhone 15 Pro Max Case – Daisy Flowers | MagSafe
41.00
POPCORNERS VARIETY PACK 28 1 OZ BAGS
15.39
White Floral Designer iPhone 13 Pro Case – Daisy Flowers | MagSafe
41.00
flav-r-pac grande classics normandy blend vegetables-4lb
10.69
Blue Mountain Designer iPhone 14 Pro Case – Indigo Hills | MagSafe
41.00