focal length 500mm astronomical refracting telescope

{"cid":"91091321","title":"Focal Length 400mm Astronomical Refracting Telescope CE OPTO-EDU","imgUrl":"https:\/\/img.chinax.com\/nimg\/54\/53\/7121c07e96854fe8e17f047c5b90-200x200-1.jpg","attrs":{"Price":"$1-$1000","Brand Name":"OPTO-EDU","Model Number":"T11.5611","Minimum Order Quantity":"1","Delivery Time":"1month","Certification":"CE","Place of Origin":"China","Payment Terms":"T\/T,West Union and Paypal","Supply Ability":"10000","Packaging Details":"Carton","Type":"Refraction","Lens Clear Aperture":"70mm","Focal Length":"400mm","Eyepiece":"Dia.31.7 K10mm, K25mm"}}

{"cid":"91199509","title":"Mount Astronomical Refracting Telescope Portable Travel Telescopes 600MM Focal Length","imgUrl":"https:\/\/img.chinax.com\/nimg\/79\/e3\/412066ba907b168013c10f4335a2-200x200-1.jpg","attrs":{"Price":"Negociation","Brand Name":"YBoptics OEM\/ODM","Model Number":"Telescope 102600","Minimum Order Quantity":"1 PCS","Delivery Time":"3-30 days","Certification":"CE FCC ROHS","Place of Origin":"Sichuan, China (mainland)","Payment Terms":"L\/C, D\/A, D\/P, T\/T, Western Union, , Paypal","Supply Ability":"30000 PCS per month","Packaging Details":"Custom","Objective lens diameter":"102mm","Focal length":"600mm","Eyepiece":"1.25 inch","Lens coating":"FMC","Focal ratio":"f\/5.9","Barov extender":"2X FMC","Zenith Mirror":"90\u00b0 full erect image","Barov Extender":"2x","Bracket":"Theodolite","Main Material":"optical glass, aluminum, iron, plastic","Storage Conditions":"\"should be stored in a sheltered, dry place, no acid gas, alkali and harmful substances around\""}}

{"cid":"91222036","title":"F30070 Monocular Space Astronomical Scope with Oblique Mirror and Aluminum Tripods","imgUrl":"https:\/\/img.chinax.com\/nimg\/f7\/6b\/7879c83326d7681750e67ae40b3d-200x200-1.jpg","attrs":{"Price":"$39.89\/pieces 5-99 pieces","Brand Name":"OEM","Model Number":"F30070","Minimum Order Quantity":"5 pieces","Place of Origin":"Jiangsu, China","Model":"F30070","Color":"Sliver","Material":"optic glass","Aperture":"70mm (2.4 inch)","Focal Length":"300mm f\/4","Oblique Mirror":"90 degrees","The Most Highly":"38cm","Eyepiece":"H6mm, H20mm","the Barlow lens":"3X","positive lens":"1.5X","Packaging Details":"Standard export carton package or according to customer's requirement.","Port":"SHANGHAI,SHENZHEN,NINGBO,GUANGZHOU,TIANJIN","Supply Ability":"20000 Piece\/Pieces per Month"}}