Red Grin is a veteran owned and operated business and Michigan's prime provider of high-end Military Simulation gear, Paintball, Airsoft and Radio Control hobby store, providing more than just products.
Gear boxes
Gear boxes and receivers for Airsoft guns
Displaying 1 to 20 (of 26 products)
7mm Metal Bearing Gear Box For Version II (MP5)
Fits all MP5, M16, G3 Series, except MP5K. Each one has bearings included, works on most other non-Classic Army brands as well.
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Fits all MP5, M16, G3 Series, except MP5K. Each one has bearings included, works on most other non-Classic Army brands as well.
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$62.00
8mm Reinforced Gearbox for Version III AEGs
8mm Reinforced Gearbox for Version III AEGs.
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8mm Reinforced Gearbox for Version III AEGs.
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$40.00
AK Type 7mm Bearing Gear Box
Fits all AK, AUG, SIG 550, MP5K series, bearings included. Compatible with most non-Classic Army brands as well.
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Fits all AK, AUG, SIG 550, MP5K series, bearings included. Compatible with most non-Classic Army brands as well.
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$74.40
$60.55
$97.50
Complete 8mm Reinforced Gearbox 400FPS Upgrade
8mm reinforced, 400FPS+ Drop-In gearbox upgrade for version 2 M4 AEGs
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8mm reinforced, 400FPS+ Drop-In gearbox upgrade for version 2 M4 AEGs
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$180.00
Complete Armory USA AK Series Version 3 Gearbox
Complete Armory USA AK Series Version 3 Gearbox.
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Complete Armory USA AK Series Version 3 Gearbox.
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$160.00
Extensive Gear Box for SR25
Gear Box for the Classic Army SR25, also compatible with most other manufacturers' SR25 models.
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Gear Box for the Classic Army SR25, also compatible with most other manufacturers' SR25 models.
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$72.50
Metal Gear Box (For MP5, M16, & G3 Series)
6mm Metal Bushing Gear Box For Version II
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6mm Metal Bushing Gear Box For Version II
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$33.60
OA PCR-97 M4 Series Factory Lower Gearbox (Fixed Stock)
Complete Olympic Arms PCR-97 M4 Series Stock Lower Gearbox.
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Complete Olympic Arms PCR-97 M4 Series Stock Lower Gearbox.
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$83.00
OA PCR-97 M4 Series Factory Lower Gearbox (Retractable Stock)
Complete Olympic Arms PCR-97 M4 Series Stock Lower Gearbox.
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Complete Olympic Arms PCR-97 M4 Series Stock Lower Gearbox.
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$83.00
Olympic Arms PCR-97 M4 Series Lower Gearbox - Case Only
Olympic Arms PCR-97 M4 Series Lower Gearbox - Case Only
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Olympic Arms PCR-97 M4 Series Lower Gearbox - Case Only
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$22.00
Olympic Arms PCR-97 M4 Series Stock Kit
Complete stock upper gearbox for the Olympic Arms PCR-97 M4 Series
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Complete stock upper gearbox for the Olympic Arms PCR-97 M4 Series
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$61.00
Olympic Arms PCR-97 M4 Series Upper Gearbox - Case Only
Olympic Arms PCR-97 M4 Series Upper Gearbox - Case Only
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Olympic Arms PCR-97 M4 Series Upper Gearbox - Case Only
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$22.00
pper Gear-Box B. M120 Upgrade Kit (MA-48)
M120 Upgrade kit - Upper gear box (MA-48) for ICS M16 Series
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M120 Upgrade kit - Upper gear box (MA-48) for ICS M16 Series
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$75.00
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