Magnaflow · New

MagnaFlow Muffler Mag SS 7X7 20 4.00/4.0

Name: MagnaFlow Muffler Mag SS 7X7 20 4.00/4.0
Brand: Magnaflow
SKU: mag12771
Price: 203.00 USD

MPN 12771 · Store SKU mag12771

$203.00

CHECK AVAILABILITY0 in supplier warehouses. Ask JuiceBuilt about availability.

Supplier stock checked 11/7/2026, 7:24:37 AM UTC. Adding a part does not reserve it.

30-day returns for unopened, unused new parts

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

Shipping & returns ↗This policy does not limit rights required by law.

Free standard shipping on eligible parts orders of $100 or more. Oversized and freight items excluded. Fitment, taxes, availability and final totals are confirmed before payment.

Product details

The MagnaFlow 7 X 7in. Round Straight-Through Performance Exhaust Muffler 12771 is engineered to enhance your ride with a healthy helping of our signature exhaust sound and dyno-proven performance thanks to its free-flowing straight-through perforated stainless steel core wrapped in stainless steel mesh and acoustic fiber fill. The reversible, universal 4/4in. diameter inlet/outlet Straight-Through layout allows you to install it in whatever orientation and configuration you see fit. However, professional installation is highly recommended. Muffler 12771s weight-optimized 7x7x20in. oval-shaped body features a satin finish that elevates the overall aesthetics of your current exhaust setup. 12771 is made of durable, corrosion resistant stainless steel and produced using cutting-edge CNC precision robotic manufacturing techniques, all backed by MagnaFlow's limited lifetime construction warranty. Magnaflow Straight-Through Performance Muffler; 4in. Center/Center; 7x20x7 Body Straight-Through Performance Muffler; 4in. Center/Center; 7x20x7 Body Straight-Through Performance Muffler; 4in. Center/Center; 7x20x7 Body MagnaFlow 4 in/4 in Center/Center; 7 in x 20 in x 7 in Body Muffler 4 in/4 in Center/Center; 7 in x 20 in x 7 in Body Muffler

Manufacturer fitment & guides

Check 12771 against the manufacturer’s application information below.

MagnaFlow manufacturer exhaust application catalog ↗

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Add your exact parts and delivery details, then continue to payment. Eligible orders show the final parts, shipping and tax total and a PayPal button here after automatic checks. Freight, oversized, custom and uncertain items go to JuiceBuilt for a quote. You are charged only after approving PayPal; supplier orders are submitted separately after verified payment.

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What is the return policy?

Request a return within 30 calendar days after delivery. New parts must be unopened and unused.

The customer pays return shipping for a change-of-mind return.

Any actual supplier restocking charge is disclosed before purchase.

Clearance and scratch-and-dent parts are final sale. No returns or refunds.

Read the full shipping & returns policy ↗

This policy does not limit rights required by law.

MagnaFlow Muffler Mag SS 7X7 20 4.00/4.0

Product details

Manufacturer fitment & guides

THE NEXT PART
OF YOUR BUILD.

Free shipping on $100+ orders.

Build with the right brands.

Find your next upgrade.

Make the whole setup work.

A few things to know.

Your build.

Delivery & checkout

Delivery address