his is a TMB Planetary wide angle eyepieces with the focal lengths 9mm. The eyepiece has a standard 1.25" (31.75mm) fitting diameter and it is ideal for use on telescopes/spotting scopes for astronomical observations.

Specifications

• Thomas Back Designed Eyepiece (TMB)
• Brand new & high quality
• Model: SWA-58-9
• 5 optical elements in 3 groups
• Internally baffled
• FOV: Wide 58 degree field of view
  
• Focal length: 9 mm
• Standard 1.25" (31.75mm) fitting diameter to the scope's eyepiece holder
• Large eye lens diameter: 21mm
• Fully multicoated green lenses for excellent image contrast and light transmission
• Fold-down rubber eyecup
• Comfortable long eye relief: 16mm
• Standard 1.25" inner thread to fit light filters
• Built with metal material
• Comes with lens caps for both ends
• Weight: 156g