Elevate your astronomical viewing experience with this precision-crafted 90mm air-spaced achromatic doublet lens. Featuring a focal length of 700mm, this high-quality optical component is ideal for constructing large aperture refractor telescopes. The air-spaced design helps minimise chromatic aberration, delivering clearer and sharper celestial observations. This manual focus lens is specifically designed for astronomical telescopes, offering excellent light-gathering capabilities. The doublet construction consists of two precisely aligned lens elements with an air gap of 0.10mm, optimised for superior optical performance. Manufactured in India, this lens comes as a complete unit ready for telescope integration. The robust construction ensures stability during observations, while the 90 mm diameter aperture allows for impressive light collection, essential for detailed astronomical viewing.