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Systema M16-A2 Bore-Up Cylinder Set for M16-A2.
Systema M16-A2 Bore-Up Cylinder Set for M16-A2.
SYSTEMA Bore-Up Cylinder Set is, in other word " Compression and Release Parts for the Higher Power".
The Stronger the spring tension, the higher the performance it put forth. On the other hand,
the "double-bumper" system employed to both piston head and cylinder head prevents the case from breaking.
It is recommendable to use M120 spring or stronger.
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