Sigma RCP-21 Drop-In WR CPL Filter for 300-600mm f/4 DG OS Sports Lens L Mount
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Sigma RCP-21 Drop-In WR Circular Polarizing Filter for 300-600mm f/4 DG OS Sports L Mount Lens

SKU: SGAK3969 MFR: AK3969
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Key Features

  • Enhance image quality with this Sigma polarizing filter, reducing glare and reflections.
  • Achieve richer colors & contrast using the circular polarizer, ideal for outdoor photography.
  • Specifically designed for the 300-600mm f/4 DG OS Sports Lens with L Mount compatibility.
  • Durable glass build ensures long-lasting performance & scratch resistance for clear shots.
  • Easy cleaning and maintenance keeps your polarizing filter in top condition for every shoot.
  • Drop-in frame design ensures secure & precise fit, optimizing filter factor and light control.
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Special Order?Estimated to Ship: 09/27/2025
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Sigma RCP-21 Specifications

  • Material

    Glass

  • Compatibility

    300-600mm f/4 DG OS Sports Lens (L Mount)

  • Filter Type

    Circular Polarizer

  • UPC Code

    198983941745

Models
Sigma RCP-21 Drop-In WR CPL Filter for 300-600mm f/4 DG OS Sports Lens L Mount

Sigma RCP-21 Drop-In WR CPL Filter for 300-600mm f/4 DG OS Sports Lens L Mount

SKU: SGAK3969

MFR: AK3969

$212.00

Special Order

Generally ships in 7-14 days, subject to availability

Tiffen 4.5" Low Light Polarizing Glass Filter

Tiffen 4.5" Low Light Polarizing Glass Filter

SKU: TF412LLPOL

MFR: 412LLPOL

$219.00

Special Order

Generally ships in 7-14 days, subject to availability

Haida M15 CPL Magnetic Round Nano-Coating Filter

Haida M15 CPL Magnetic Round Nano-Coating Filter

SKU: HAHD4365

MFR: HD4365

$198.00

Temporarily On Backorder

Although this item is temporarily on Backorder, you can order it now and it will ship as soon as it arrives. Your card will only be charged once item is shipped.

Circular Filter Size-114mm (4.5")150mm
Coating-NoneMulti-Coated
MountDrop-In FrameDrop-In FrameDrop-In Frame
Polarizer TypeCircularLinearCircular

About Sigma RCP-21

A drop-in PL filter that allows effect adjustment via dial while attached to the lens. It helps reduce reflections from glass and water surfaces and enhances contrast in landscape photography.

Sigma RCP-21 Features

  • Adjustable PL filter with dial for effect control
  • Reduces reflections from glass and water surfaces
  • Enhances contrast in landscape photography

Warranty Information

This product has a limited warranty of 12 months for parts and 12 months for labor.

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Key Features

  • Enhance image quality with this Sigma polarizing filter, reducing glare and reflections.
  • Achieve richer colors & contrast using the circular polarizer, ideal for outdoor photography.
  • Specifically designed for the 300-600mm f/4 DG OS Sports Lens with L Mount compatibility.
  • Durable glass build ensures long-lasting performance & scratch resistance for clear shots.
  • Easy cleaning and maintenance keeps your polarizing filter in top condition for every shoot.
  • Drop-in frame design ensures secure & precise fit, optimizing filter factor and light control.

What's in the box:

  • Sigma RCP-21 Drop-In WR Circular Polarizing Filter
  • Sigma 1 Year Limited Warranty