Optec-DSI 3.5x24tpi to PlaneWave SecureFit Adapter (19920)

Name: Optec-DSI 3.5x24tpi to PlaneWave SecureFit Adapter (19920)
Brand: Optec
SKU: 19920
Price: 58.9 USD
Availability: InStock
Rating: 4.4 (5 reviews)

Optec-DSI 3.5x24tpi to PlaneWave SecureFit Adapter (19920) - Main image

$58.9 ~~$95~~ In stock

Category: Astrophotography Accessories

Description

Optec-DSI 3.5x24tpi (male) thread adapter to PlaneWave SecureFit.

Specifications

Outside Diameter: 4.75" (120.7mm)
Overall Height: 0.85" (21.6mm)
Clear Aperture: 3.25" (82.6mm)
Back-focus Usage: 0.16" (4.0mm)

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.4 / 5 · 5 reviews)

Eli ★★★★★ Oct 21, 2026

Went from a frustrating adapter jumble to a solid, wobble-free connection—the 3.25-inch clear aperture on this one means zero vignetting even with my full-frame camera. It's exactly the precision piece I needed.

Eli ★★★★★ Oct 18, 2026

The clear aperture of 82.6mm works perfectly, giving me full illumination on my sensor without any vignetting. It threaded on smoothly and locks tight with no play, exactly what I needed for a secure connection.

David S. ★★★★★ Oct 18, 2026

Fit was spot-on with my PlaneWave setup, and that 3.25" clear aperture didn't vignette my full-frame sensor at all. Machining is clean and threads engaged smoothly without any wobble or play. Exactly what I needed to mate my 3.5x24tpi scope to the SecureFit without shims.