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AirsoftParts AEG M4 Air Seal Upgrade Set
AirsoftParts air seal set for M4 offers a cost-effective combination of upgrade parts for the air seal system of M4, MK18 AEG rifles and other AR15-platform guns with inner barrels up to 400 mm. The set includes a POM piston head, silent cylinder head, ported cylinder and 21.4 mm nozzle. The individual parts form a matched set for improving the performance of your gun.
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AirsoftParts Air Seal Set for M4 AEG
AirsoftParts air seal set for M4 combines four important AEG air seal components in one cost-effective set. It includes a POM piston head, silent cylinder head, ported cylinder and a 21.4 mm nozzle. This combination is designed for M4-type AEG rifles with inner barrels up to 400 mm and provides a practical solution when replacing a major part of the air seal system or building a new configuration. The ported cylinder adjusts the usable air volume, while the piston head, cylinder head and nozzle form interconnected parts of the compression system. Proper operation depends not only on their mutual air seal, but also on compatibility with the specific gun model, inner barrel length and hop-up chamber used. In particular, the 21.4 mm nozzle length should be compared with the original nozzle before installation, as individual M4 models may use different dimensions depending on the manufacturer and design.
Key Features
Four Air Seal Components in One Set
The set combines a piston head, cylinder head, cylinder and nozzle, so there is no need to purchase the individual components separately.
POM Piston Head
The set includes a POM piston head that operates inside the cylinder and uses its seal to generate the required air pressure as the piston moves.
Silent Cylinder Head
The silent cylinder head forms the front section of the compression chamber, and its design also helps dampen the mechanical impact of the piston assembly.
Ported Cylinder
The ported cylinder has a reduced usable working volume compared with a full cylinder, allowing the amount of compressed air to be matched to the corresponding inner barrel configuration.
21.4 mm Nozzle
The set includes a 21.4 mm nozzle. Before installation, it is advisable to verify the required length for the specific combination of gearbox and hop-up chamber used in the M4.
Technical Specifications
- Type: air seal set for AEG
- Platform: M4 / AR15
- Piston head: POM (flat)
- Cylinder head: silent (duralumin)
- Cylinder: ported (for 200–400 mm inner barrels)
- Nozzle length: 21.4 mm (duralumin)
Package Contents
- 1× POM piston head
- 1× silent cylinder head
- 1× ribbed ported cylinder
- 1× 21.4 mm nozzle
Frequently Asked Questions (FAQ)
Is the Set Designed for All M4 AEG Rifles?
The set is designed by the manufacturer for M4-type AEGs, but specific compatibility depends on the design of the particular model. It is especially important to verify the 21.4 mm nozzle length and the compatibility of the other components with the gearbox and hop-up chamber used.
What Does the Set Include?
The package includes a POM piston head, silent cylinder head, ported cylinder and 21.4 mm nozzle. These are four interconnected components of the AEG air seal system.
Why Is It Important to Check the Nozzle Length?
The correct nozzle length affects how it works with the hop-up chamber and hop-up bucking. This set uses a 21.4 mm nozzle, so its dimensions should be compared with the original part or the requirements of the specific gun before purchase.
Should the Air Seal Be Checked After Installation?
Yes. After installation, it is advisable to check the air seal of the entire compression system and the free movement of the individual components. Proper operation depends not only on the parts themselves, but also on their installation and correct matching with the specific AEG build.
| Variants | AEG M4 |
| Color | Silver |
| Body/receiver material | Metal |
| Gearbox version | V2 |
| Piston head | Plastic |
| Nozzle | Metal |