LPA SPS21RU6F Micrometer Sight Set for Rock Island 1911 / Armscor – Fiber Optic

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LPA SPS · Fiber Optic · Rock Island 1911 / Armscor
SPS21RU6F: Rock Island / Armscor – not Ruger Mark IV The exact LPA code SPS21RU6F is assigned to Rock Island 1911 / Armscor in the official LPA order table. The previous shop assignment to Ruger Mark IV was therefore critically wrong for purchasing.
The 6F version is listed as a black rear sight with a red fiber optic front sight. Fiber bundles ambient light; it is not a self-illuminating night sight.

Black-Raptor Buying Guide
This set makes sense for buyers who want to equip a suitable Rock Island / Armscor 1911 with adjustable sights and a clearly visible red front dot. The real sight mount is decisive – not the optical similarity to other 1911 or Ruger models.


Fits well if … … your pistol belongs to the confirmed Rock Island / Armscor family, the mount and front sight base are unchanged, and you prefer a light-gathering front dot.


Fits less if … … you own a Ruger Mark IV, expect a self-illuminating night solution, or the sight mount has already been modified.


Variant selection and compatibility


Manufacturer code SPS21RU6F is the authoritative LPA identifier. Shopify SKU 806246 is a separate shop/supplier identifier.


Platform Rock Island 1911 / Armscor according to the official LPA table. Do not transfer to other 1911 mounts.


6F version Black rear sight picture plus red fiber optic front sight. The front dot benefits from available light but does not produce its own illumination.


Check before purchase weapon variant, existing sight mount, and any modifications. In case of doubt, a professional measurement/fit check is more sensible than buying by model name.


Limits, disadvantages, and avoiding bad purchases

No Ruger Mark IV set: The old assignment was
wrong.
No universal 1911 set: 1911 models use different sight mounts.
Fiber has limits: In very dark environments without ambient light, the contrast advantage decreases significantly.
Assembly condition matters: Reworked or already converted slides may differ from the manufacturer assignment.

Technical data with practical interpretation


Series LPA SPS · adjustable complete sight set.


Code SPS21RU6F · unique manufacturer code for this variant.


Compatibility Rock Island 1911 / Armscor according to LPA order table.


Sight picture 6F: black rear sight, red fiber-optic front sight – for quick front focus in available light.


Scope of delivery
Confirmed product type: sight set consisting of adjustable rear sight and matching front sight. Firearm and separate mounting tool are not included; additional tools only if specified by LPA in the specific packaging.
FAQ
Does SPS21RU6F fit Ruger Mark IV? No. LPA assigns SPS21RU6F to Rock Island 1911 / Armscor. What does 6F mean? The LPA table lists this variant with black rear sight and red fiber-optic front sight. Does the front sight glow in the dark by itself? No. Fiber-optic uses available ambient light and is neither tritium nor luminova. Does the set fit every 1911? No. The specific sight mount of the confirmed platform is decisive.
Black Raptor · Code before model association
SPS21RU6F is the fiber variant for Rock Island 1911 / Armscor. Those with Ruger Mark IV or another 1911 mount need a different, precisely assigned LPA code.