Elite Force H&K MP7 A1 Airsoft Gen4 Gun - Black Replacement Goggle Parts Spiral Porting for great upgrade

Spiral Porting for great upgrade over stock barrels

but appears to be done poorly or it is simply coming off

Dimensions: 210mm x 150mm

Rather than using the tired method of heat-formed EVA

Elite Force H&K MP7 A1 Airsoft Gen4 Gun - Black Replacement Goggle Parts Spiral Porting for great upgradeFeatures: Fully trademarked H&K Heckler & Koch Engraving Compact design; great as a sidearm or primary weapon Realistic, hard kick blowback Extreme high quality build and detailed finish Adjustable hopup for optimized range Fully automatic and semi automatic firing Telescopic two position retractable stock with rubber buttpad Metal rails, flashhider, magazine, fire selector, slide release, iron sight and retractable stock FPS Range: 380 430 For H&K