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Extension tubes

Topiky 2 in extension tube, 60 mm

A 60 mm 2 in extension tube in anodised aluminium with two brass-tipped locking screws to stop an inserted barrel slipping.

Topiky 60 mm 2 inch telescope extension tube

Topiky 2 in extension tube, 60 mm

A 60 mm 2 in extension tube in anodised aluminium with two brass-tipped locking screws to stop an inserted barrel slipping.

Length
60 mm, from the title · Not distinguished from the physical length in the listing
Barrel and thread fittings
2 in
Internal blackening
Black anodised, described as avoiding unwanted reflections
Clamping method
Two thumbscrews with brass locking tips, per the maker
Rigidity
Not published by the maker.
Material
Aluminium alloy
Amazon reference
B07VWQRT4P (same reference on 5 Amazon marketplaces)
EAN
0781593971556
  • Brass tips under the thumbscrews prevent an inserted barrel being marked
  • Two screws rather than one, which holds a heavy eyepiece more securely
  • The listing does not say whether 60 mm is the physical length or the optical path added

Best for: A 2 in focuser that needs a substantial, inexpensive extension

≈ €24
Check price on Amazon

Specifications

Length
60 mm, from the title · Not distinguished from the physical length in the listing
Barrel and thread fittings
2 in
Internal blackening
Black anodised, described as avoiding unwanted reflections
Clamping method
Two thumbscrews with brass locking tips, per the maker
Rigidity
Not published by the maker.
Material
Aluminium alloy
Amazon reference
B07VWQRT4P (same reference on 5 Amazon marketplaces)
EAN
0781593971556

Sixty millimetres of extension

A substantial step, and in a 2 in fitting. For a telescope whose focal plane sits well outside what an eyepiece can reach, a single long sleeve is simpler than stacking several short ones — fewer joints, less flexure.

The brass tips

Two thumbscrews with brass locking tips. That is a real detail: a bare steel screw dents the barrel it clamps and pushes the accessory off axis, and brass spreads the load without marking. A compression ring would be better still.

The ambiguity worth noting

Sixty millimetres is published without saying whether it is the outside length or the optical path added. The two differ by however deep the barrel seats, and a back focus calculation needs the second figure.

The finish

Black anodised, described as preventing unwanted reflections. That is an outside finish; whether the bore is treated is not stated, and the bore is where it matters.

Availability

German, French, Italian and Spanish Amazon stores ran from 24 € to 36 € on the day of the survey.

British Amazon catalogue holds a record for it that nobody is selling.

American Amazon store gave no result whatever, so the buy button there opens a search rather than an empty page.

Figures as Keepa reported them on the day this page was last updated. Stock and pricing shift without warning.

Prices quoted in this text were read on 17 September 2026. The live price is at the top of the page.

What this fits

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The rest of this rack

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