You have a 3 inch focuser or accessory from Starlight Instruments and a telescope or part from William Optics, but the threaded connection does not match each other. If you are looking for an adapter William Optics male to 3 inch female, this is the part from Starlight Instruments that connects both.<\/p>\n\n\n\n
On one side there is a 3 inch female connection with internal thread, on the other side a male connection with external thread in the size of William Optics. This brand is especially well known from Refracting telescopes<\/a>, And it is precisely in that combination that this progression comes in handy.<\/p>\n\n\n\n Before ordering, find out which connection your telescope has. Measure the diameter of the wire and check the manual for your telescope. Male and female connectors are easily interchangeable: male is the outer thread, female is the inner thread. If you\u2019re unsure, feel free to call, email, or message us; we\u2019ll be happy to help you.<\/p>\n\n\n\n For specific William Optics telescopes, there are also ready-made solutions, such as the focus adapter for the GT102<\/a> and the adapter for the FLT 110<\/a>.<\/p>","protected":false},"excerpt":{"rendered":" Extension piece from Starlight Instruments with 3 inch inner thread to William Optics outer thread, so that parts from both brands fit together.<\/p>","protected":false},"featured_media":113660,"comment_status":"open","ping_status":"closed","template":"","meta":{"_acf_changed":false},"product_brand":[3291],"product_cat":[499,56],"product_tag":[],"class_list":["post-113661","product","type-product","status-publish","has-post-thumbnail","product_brand-starlight-instruments","product_cat-adapters","product_cat-telescoop-accessoires","first","instock","taxable","shipping-taxable","purchasable","product-type-simple"],"bundled_by":[],"bundle_stock_status":"instock","bundle_stock_quantity":null,"bundle_virtual":false,"bundle_layout":"","bundle_add_to_cart_form_location":"","bundle_editable_in_cart":false,"bundle_sold_individually_context":"","bundle_item_grouping":"","bundle_min_size":"","bundle_max_size":"","bundle_price":[],"bundled_items":[],"bundle_sell_ids":[],"acf":[],"jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":113536,"url":"https:\/\/www.telescoop.nl\/en\/adapter-voor-william-optics-flt-110-115-x-125-mm-past-op-feather-touch-3-inch-starlight\/","url_meta":{"origin":113661,"position":0},"title":"Adapter for William Optics FLT 110, 115 x 1.25 mm, fits on Feather Touch 3 inch | Starlight","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Adapter with 115 x 1.25 mm inner thread to connect a 3 inch Feather Touch from Starlight Instruments to a William Optics FLT 110.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/20545_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/20545_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/20545_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113663,"url":"https:\/\/www.telescoop.nl\/en\/focuseradapter-voor-william-optics-gt102-3-inch-starlight\/","url_meta":{"origin":113661,"position":1},"title":"Focus adapter for William Optics GT102, 3 inch | Starlight","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"With this you can mount a 3 inch focuser from Starlight Instruments on a William Optics GT102, with room for larger cameras and accessories.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/74105_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/74105_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/74105_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113655,"url":"https:\/\/www.telescoop.nl\/en\/focuseradapter-voor-william-optics-flt-35-inch-starlight\/","url_meta":{"origin":113661,"position":2},"title":"Focus adapter for William Optics FLT, 3.5 inch | Starlight","author":"Info telescoop","date":"09-10-2026","format":false,"excerpt":"Adapter to attach a 3.5 inch focuser from Starlight Instruments, such as a Feather Touch, to a William Optics FLT refractor.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/73954_1.jpg?resize=350%2C200&ssl=1","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/73954_1.jpg?resize=350%2C200&ssl=1 1x, https:\/\/i0.wp.com\/www.telescoop.nl\/wp-content\/uploads\/2026\/10\/73954_1.jpg?resize=525%2C300&ssl=1 1.5x"},"classes":[]},{"id":113623,"url":"https:\/\/www.telescoop.nl\/en\/focuseradapter-voor-william-optics-66-mm-refractor-past-op-feather-touch-starlight\/","url_meta":{"origin":113661,"position":3},"title":"Focus adapter for William Optics 66 mm refractor, fits Feather Touch | Starlight","author":"Info 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