FN 509® V4 MIL / LEO to Holosun 509T



**This plate will not work with the Holosun HE509-RD ACSS Vulcan
(6 customer reviews)

In stock

Frequently Bought Together

Do-It-Right Bundle: Check all three of these products and hit "add to cart" for a 15% discount!

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Price for all three: $143.95

The C&H Precision plates are designed, manufactured and shipped from our small family owned business in Coastal Georgia.  Each plate is precision machined to the tightest tolerances on HAAS CNC machines and each plate goes through multiple quality checks before shipping to our customers.


Thickness:  V4 MIL / LEO Plates are .095″ to .099″ thick

Material: Plates are made from 6061 aluminum.  All mounting hardware is Stainless Steel

Finish:  Plates are MIL-SPEC Type III Hard Anodized – Black


Qty 1 – Optic Plate

Qty 2 – 6-40 Plate Mounting Screws

Additional information


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6 reviews for FN 509® V4 MIL / LEO to Holosun 509T

  1. Jonathan Chen (verified owner)

    Strange as I experienced logistical issues as well. That aside the piece fits well but my 509t compact has a o ring indent already, why couldn’t this be replicated on the plate. The 2 smaller o-rings must be proprietary but they seem to leave a tony gap between the plate and slide and prevent it from being just flush. Thread locker is setting, will see if there is change at the range once cured.

  2. Cody Triplett (verified owner)

    Great product! This is my second plate from you all but i have a question that i have sent twice to customer service and i have posted it on your all’s instagram and i have not gotten a response to my question. I would love a response. I asked what type of acetone do you all use to clean all the parts that need to be cleaned before mounting a plate? The installation videos do not say at all what type and there are mean different types. You go into great detail about installation for types of screws, lock tight and other things. Minus what type of acetone to use.

  3. Kyle Paquet (verified owner)

    Shipped fast! Not sure what the other reviewer did wrong.. sounds like he didn’t use the included o-rings that act as a buffer between the plate and the slide if his plate was loose. Mine fit like a glove, is secure and had no shift in zero. Highly recommend to anyone.

  4. Colby Waterworth (verified owner)

    It took 2 weeks from the time I placed my order until the time I recieved it. I had selected 2 day shipping. Once it got here I installed per the instructions and used the included hardware. This was a no go. Once the screws were torqued to their value the plate was still loose in the MRD cut. The heads of the supplied screws were bottoming out on the top of the slide with their taper(plate must be too thin). I then used the screws that were included in the holosun packaging and at least the plate didnt have any shifting that I could notice. Now after my 2nd range trip I can see that the plate has been shifting in the cut. This was also noticable when my zero had shifted ~4″ at 25yds. I can notice the shift when I hold the optic and see the plate flexing. Maybe a slightly thicker steel plate would be better.

  5. tomalbut1 (verified owner)

    Bought it with express shipping. No tracking update two weeks later. After asking a few times politely for when it may arrive all I am told is “its going out tomorrow” followed by “We were attempting to get some in yesterday”. If the first response was I’m sorry we dont have any, or we’re still waiting for them to come in I wouldn’t be in this position. The product is probably good, but it doesn’t look like I’ll ever know.

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