UMAREX SD4 Rifle Silencer – Dual-Thread Airgun & Airsoft Moderator
£60.00
High-performance suppression for serious shooters. Airgun or airsoft—this one does it all.
The UMAREX SD4 Silencer is a premium, multi-purpose suppressor designed for airgun and airsoft use. Engineered for maximum efficiency, it features a six-chamber internal design and a precision CNC-machined aluminium body that delivers an impressive sound reduction of up to 25 dB, especially on higher-powered airguns.
Whether you're running a .177, .22, or .25 calibre air rifle—or using 6mm BBs in your airsoft rifle—the SD4 delivers serious sound suppression while maintaining a lightweight and durable profile.
Dual-Thread Compatibility Included:
To keep things simple, the SD4 ships with two popular thread adapters:
½″-20 UNF (for most air rifles)
14mm CCW (left-hand) (common on airsoft rifles)
Please Note:
Airsoft users: If your gun has a particularly aggressive hop-up, you may experience BB clipping against the internal baffles.
UK customers: This is a working silencer and cannot be posted to your home address, regardless of whether it's being used for airsoft or airgun applications. Collection in-store or RFD transfer only. See our shipping terms for full details.
Key Features:
Suitable for 4.5mm (.177), 5.5mm (.22), 6.35mm (.25) airguns and 6mm airsoft BBs
Dual-thread adapters included: ½"-20 UNF and 14mm CCW
Six-chamber internal design for superior sound reduction
Fully serviceable: Removable interlocking baffles for easy maintenance
CNC-machined aluminium construction with a sleek satin finish
Secure screw caps on both ends
Ideal for sub-12ft/lb air rifles and mid-level HPA airsoft setups
Specifications:
Length: 200 mm
Diameter: 35 mm
Weight: 190 g
Bore Diameter: 8.5 mm
Construction: CNC-Machined Aluminium
Finish: Satin
Thread Compatibility: ½"-20 UNF & 14mm CCW (LH)
Serviceable: Yes – user-removable baffle system
Quiet, clean, and ready for work. The SD4 is a great upgrade for those who want to tame the bark of their air rifle or airsoft gun—without compromising performance or versatility.
Quantity
Important Notice
Important Notice for the Purchase and Delivery of Airguns, Pressure Components of Airguns, and Moderators
Effective Compliance with the Violent Crime Reduction Act 2006 (VCRA): Sections 31 and 32
Under the provisions of Sections 31 and 32 of the Violent Crime Reduction Act 2006, which were enacted through "The Violent Crime Reduction Act 2006 (Commencement No 3) Order 2007: firearms measures," specific regulations now apply to air weapons, their Pressure-Bearing component parts, and certain accessories.
Key Points to Note:
Restricted Items:
- Airguns: All airguns are classified as restricted items.
- Pressure-Bearing Parts of Airguns: This includes barrels, cylinders, reservoirs, and pistons.
- Functional Moderators (Silencers/Suppressors): Moderators that reduce the sound of discharge are also classified as restricted items.
Definition and Registration:
- Component Parts: While the VCRA does not explicitly define "component parts," the Home Office interprets this to include pressure-bearing parts such as barrels, cylinders, reservoirs, and pistons.
- Accessories: Only moderators (silencers) require registration by dealers.
Legal Requirements for Transfer:
- In-Person Transfer: It is an offence under the VCRA to transfer these restricted items through standard postal systems or to the end customer directly without the presence of both the buyer and either the seller or a representative of the seller.
- Representatives of the Seller: This can be:
- An employee of the seller who is a registered firearms dealer (RFD).
- Another RFD authorized by the seller.
- An employee of the authorized RFD.
Collection and Delivery Options:
- Collection from Store: Customers are encouraged to collect their restricted items directly from the store where purchased.
- Transfer to Another RFD: Items can be transferred to a local RFD for collection, though the receiving RFD may charge a fee for this service.
- Home Delivery: We offer home delivery through our in-house team to some areas of the UK. However, please note that this service has location restrictions and incurs higher costs due to the need for dedicated transport, making it more expensive than a standard RFD transfer.
For more detailed guidance on purchasing and receiving VCRA Restricted Transfer items, please refer to our comprehensive guide here: VCRA Restricted Transfer Items Buying Guide

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