HKS 3306-RA076 Inner Muffler Silencer 115mm Universal Tip Black SUS304 Bolt-On

Vehicle Fitment

• Universal - fits any HKS exhaust system equipped with a 115mm muffler tip

Fitment Notes

• Tip inner diameter must be 115mm for this silencer to fit correctly - this is the universal 115mm size, distinct from the 94mm and 120mm silencer variants; confirm your muffler's tip outer diameter matches 115mm before ordering
• Unlike the profile-specific silencers in the HKS inner silencer range (which are shaped for particular tip styles such as Hi-Power or Drager), the 3306-RA076 is designated Universal and is designed to fit any HKS muffler with a 115mm tip regardless of the specific tip profile
• Installation requires M6 mounting holes in the muffler tip - the silencer is secured via M6 hardware; confirm your muffler tip has pre-drilled M6 holes or that you are able to add them before ordering
• The silencer is fully removable - it can be unbolted and taken out whenever maximum exhaust flow is preferred, such as for track use, without any permanent modification to the exhaust system
• Finish is black painted - some surface discoloration from exhaust heat at the tip is normal over time and does not affect silencer function

Features

• Reduces exhaust sound output by approximately 7 dB on average - consistent with the rest of the HKS inner silencer range, the 7 dB reduction represents a perceptible halving of apparent loudness, making the exhaust noticeably quieter for street use, residential areas, or noise-restricted environments without requiring permanent changes to the system
• Universal 115mm fitment covers the full range of HKS mufflers using this tip diameter - a single silencer purchase covers any 115mm HKS tip without needing to identify a specific profile variant, simplifying part selection
• Bolt-on installation via M6 hardware - the silencer inserts into the tip opening and secures with the included M6 bolts and nuts using basic hand tools; removal is equally simple when switching to unsilenced operation
• SUS304 stainless steel construction provides the corrosion resistance and thermal stability required in the exhaust tip environment - the same alloy standard used in the HKS exhaust systems this silencer accompanies
• Black painted finish blends cleanly inside the tip opening, maintaining a tidy visual presentation at the exhaust exit without a raw metal appearance
• Fully reversible - no permanent modification to the exhaust system is required to install or remove this silencer; the exhaust returns to full unsilenced performance immediately upon removal

Specifications

• Part Number: 3306-RA076
• HKS Product Name: INNER SILENCER D115 UNIVERSAL
• Compatible Tip Diameter: 115mm
• Compatible Tip Style: Universal (any HKS 115mm tip)
• Material: SUS304 stainless steel
• Finish: Black painted
• Fitment: Universal (any HKS muffler with 115mm tip)
• Average Sound Reduction: ~7 dB
• Mounting: M6 bolt-on (M6 holes required in muffler tip)
• Quantity: 1 inner silencer

Included Components

• 1x Inner muffler silencer, 115mm universal, black painted, SUS304
• M6 bolts and nuts for installation

Product Description

The HKS 3306-RA076 is the Universal inner muffler silencer for HKS exhaust systems with a 115mm tip diameter - designated by HKS as the INNER SILENCER D115 UNIVERSAL. Unlike the profile-specific silencers in the HKS lineup (such as the Hi-Power or Drager-specific variants), the 3306-RA076 is sized and shaped as a universal fit for the 115mm tip diameter, covering any HKS muffler that uses this tip size without requiring identification of a specific tip profile. The silencer reduces exhaust sound output by approximately 7 dB on average - a perceptible halving of apparent loudness - making it an effective noise management solution for street driving, residential areas, or noise-regulated environments.

Installation requires M6 mounting holes in the muffler tip, which the silencer uses to secure itself with the included M6 hardware. Some HKS mufflers have these holes pre-drilled from the factory, while others may require them to be added. The silencer is fully removable by unbolting the M6 hardware, immediately restoring the unsilenced exhaust character and full flow for track use or any situation where noise reduction is not needed. No permanent modification to the exhaust is required at any stage.

The silencer is constructed from SUS304 stainless steel with a black painted finish, consistent with the standard for the HKS inner silencer range at this diameter. M6 bolts and nuts are included.