Explore Scientific 1.25" 3X Focal Extender

The Explore Scientific 1.25" 3x Focal Extender triples your eyepiece magnification in a single step, pushing mid-range eyepieces into high-power planetary territory while preserving their comfortable eye relief. A 15mm eyepiece becomes a 5mm equivalent — sharp, high-contrast views of Jupiter's cloud bands and Saturn's ring divisions without squinting through a tiny lens.

Built around the same telecentric 4-element optical design used across the entire Explore Scientific focal extender line, the 3x delivers flatter fields and sharper edges than conventional Barlow lenses. EMD-enhanced multi-coatings on all air-to-glass surfaces maximize light transmission, and edge-blackened elements suppress internal reflections for clean contrast. Magnification stays consistent regardless of spacing in the optical path.

The lightest and most compact model in the lineup at 249g and 93mm, the 3x adds minimal weight to your focuser assembly. Threaded for standard 1.25" astronomy filters.

Key Features

• 4-element telecentric optical design with EMD-enhanced fully multi-coated optics
• Triples magnification while preserving full eye relief from the base eyepiece
• Lightest and shortest focal extender in the lineup (249g / 93mm)
• Non-marring compression ring clamp and double-tapered insert barrel
• Threaded for 1.25" astronomy filters

Ideal For

• Planetary observers — reach high magnification from a comfortable, long-eye-relief eyepiece without buying a dedicated short-focal-length model
• Compact setups — the smallest and lightest extender minimizes balance shift on lightweight telescopes
• Filling magnification gaps — a single 3x extender with two eyepieces covers six effective focal lengths