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Aero Precision

Ar-15/.308 Ooops Kit - Ar-15/M5 Fix-It Kit

Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.

Aero Precision

Ooops Kit for AR-15 and

Includes Commonly

Lost small parts for finishing

Compatible Ar15,

AR15, M4E1, and M5 builds

Contains Takedown

Pin detents, springs, and related

Includes Buffer

Retainer, selector, and trigger pin

$17.99
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SKU: 100036985

Overview

Built for builders who want a practical backup on hand, this parts kit covers the small components most likely to go missing during an AR-style assembly or repair. It is compatible with AR15, M4E1, and M5 builds, making it a straightforward option for keeping a project moving when a detent, spring, or pin disappears. The assortment includes multiple commonly lost pieces, along with a 4-40 set screw for threaded takedown pin detent holes and a threaded roll pin. For hunters and shooters who maintain their own rifles, it offers a simple way to reduce downtime without adding unnecessary extras.

Why Hunters Choose the Aero Precision

Includes Commonly

Lost small parts to help

Compatible Ar15,

AR15, M4E1, and M5 builds

Multiple Spares

For several hardware items

Includes Parts

For takedown, safety selector, and

Aero Precision

Branded kit for build completion

Key Features

  • Aero Precision Ooops Kit for AR-15 and M5 builds
  • Includes commonly lost small parts for finishing a build
  • Compatible with AR15, M4E1, and M5 builds
  • Contains takedown pin detents, springs, and related hardware
  • Includes buffer retainer, selector, and trigger pin components
  • Supplies 4-40 set screws for threaded takedown pin detent holes

Best Used For

  • AR-15 or M5 builders replacing commonly lost small parts during assembly
  • Home gunsmiths who want spare pins, springs, and detents on hand
  • Owners of AR15, M4E1, or M5 builds needing compatible replacement hardware
  • Bench setups where a missing detent or spring would otherwise stop progress

Pros

  • Includes commonly lost small parts to help finish AR builds
  • Compatible with AR15, M4E1, and M5 builds
  • Provides multiple spares for several hardware items
  • Includes parts for takedown, safety selector, and buffer retainer assemblies
  • Aero Precision branded kit for build completion

Considerations & Trade-offs

  • This kit is limited to commonly lost small parts; it is not a complete build or repair solution for an AR-15/M4E1/M5 project.
  • Compatibility is stated for AR15, M4E1, and M5 builds, so it is intended for those platforms rather than a universal parts assortment.
  • The contents are focused on replacement hardware in small quantities, so it is best suited for recovering from a missing part rather than stocking a full bench inventory.
  • The included 4-40 set screw is specifically for a threaded takedown pin detent hole, which makes it a targeted fix rather than a one-size-fits-all substitute.

Suggested Comparisons

  • AR-15 lower parts kits
  • AR-15/M4E1/M5 build components
  • Small replacement hardware kits for rifle assembly
  • Spare pins, springs, and detents kits

Suggested Accessories

  • Small parts organizer
  • AR-15 armorer's tool
  • Bench mat
  • Spare parts kit

Frequently Asked Questions

What builds is this Ooops Kit compatible with?

According to the product description, the parts are compatible with AR15, M4E1, and M5 builds.

What parts are included in the kit?

The kit includes takedown pin detents, takedown pin springs, bolt catch roll pins, trigger/hammer pins, safety selector springs, safety selector detents, buffer retainers, buffer retainer springs, disconnector springs, 4-40 set screws for a threaded takedown pin detent hole, and a threaded roll pin.

How many of each part come in the kit?

The listed quantities are: takedown pin detent (4), takedown pin spring (4), bolt catch roll pin (2), trigger/hammer pin (2), safety selector spring (2), safety selector detent (2), buffer retainer (2), buffer retainer spring (2), disconnector spring (2), 4-40 set screw (2), and threaded roll pin (quantity not specified in the provided text).

Is this kit meant for a full build or just replacement parts?

The description says it is for the commonly lost parts needed to finish a build, so it is presented as a small parts replacement kit rather than a complete build kit.

Does the product data specify the material or dimensions of the parts?

No. The provided product data does not list material, size, or dimensional specifications for the parts.