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Strike IndustriesMuzzle DevicesValue Tier

Micro Threaded Comp CIRCLE

Universal 1/2x28 micro comp that uses an O-ring for timing and retention on shouldered barrels.

Price: $42
Weight: 0.4 oz
Brand: Strike Industries
Category: Muzzle Devices

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Features

•Any 1/2x28 9mm or .357 SIG barrel
•O-ring timing and retention
•AISI 1144 steel
•0.64 inch long

Capability Boosts

Mobility+1

Recommended For

Vehicle Operations

Concealed Carry

everyday carry

pocket carry

deep concealment

backup gun

+5 more

Where to Buy

Compare current prices and availability from retailers we work with.

RetailerPriceAvailabilityUpdatedShop

Optics Planet

Strike Industries Micro Threaded Compensator Circle Black One Size

$45.95

Unknown

1d ago

View offer

Price History

90-day low $41.36

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Overview

The CIRCLE is a 0.35-ounce AISI 1144 steel micro comp for 1/2x28 9mm and .357 SIG barrels. Strike lists universal threaded-barrel fitment rather than specific Glock slimline models.

On a shouldered barrel, the supplied O-ring clocks and retains the comp. Strike warns that the O-ring cannot work on a shoulderless barrel; that setup instead requires red Loctite and routine retention checks.

Key Features

O-ring timing and retention on shouldered barrels
Red-threadlocker fallback for shoulderless barrels
AISI 1144 steel with QPQ finish
0.64-inch length and 0.35-ounce weight
Universal 1/2x28 fitment

Pros

+Published weight is 0.35 oz
+O-ring makes timing simple on a shouldered barrel
+Steel body doubles as a durable thread protector

Cons

−Manufacturer does not name Glock 43, 43X, or 48 fitment individually
−Shoulderless barrels require red threadlocker instead of the O-ring

Detailed Specifications

Material: AISI 1144 steel with QPQ finish
threading: 1/2x28
compatibility: Any 1/2x28 9mm or .357 SIG threaded barrel
retention: Included O-ring times and retains on shouldered barrels; red threadlocker required when no shoulder exists