These are made of precision machined aluminum with black anodizing. An M3 Allen wrench is included with each par focal ring. 

Par focal rings are used for several purposes:

    If you would like to make your non-par focal eyepiece set par focal you can put one of these rings on each eyepiece and adjust the height so that all eyepieces are at the same focus point. Now, when you swap eyepieces, you won't need to refocus every time! 

   They are also extremely useful when used with a flip mirror for photography. To use a par focal ring with a flip mirror you would first use the telescopes focuser to put your attached camera in perfect focus, now slide a ring over the eyepiece of your choice and raise and lower the eyepiece in the holder until it is perfectly in focus. Once you find the focus point that is perfectly matched to the camera slip the ring down and lock it in place using the included wrench. Now you can focus using the eyepiece . This is much easier than a dim focus screen. You just flip the mirror and take a picture! Leave the ring in place on the eyepiece and you can always quickly and easily pop it back in for photography

Item Name: 2 inch Par Focal Ring
Item Number: PFR2
Price: $6.00

   No light cone obstruction with this adapter in your 2" focuser. Constructed of precision machined black-anodized aluminum with nickel-chrome plated brass barrel, captive set screw recess, and threading for your T-ring. Attach your T-ring to your DSLR or SLR, thread the DP2 onto your t-ring and slip this into your 2" focuser or 2" Barlow, and secure it. You can now use your telescope at prime focus! Made in Japan

   Need some extra out focus travel with your low profile focuser, or lower power eyepieces, and need a compression ring to protect your eyepieces from barrel marks? Here is the adapter for you. Adds 50 mm or 2" of out focus travel. Constructed of precision machined black-anodized aluminum with nickel-chrome plated brass barrel, 2" brass compression ring, 1 set screw, and threading for 2" filters.

Item Name: Antares 2 inch Extension Tube w/ compression ring 
Item Number: ET2C
Price: $25.00

  The T2 threads onto the existing visual backs of  8" &  9.25" SCT's. You can use your premium diagonals on your SCT with out having to buy a special SCT only diagonal. Constructed of precision machined black-anodized aluminum, 2 set screws to sourly hold your diagonal.  

T2C

  The T2 threads onto the existing visual backs of  8" &  9.25" SCT's. You can use your premium diagonals on your SCT with out having to buy a special SCT only diagonal. Constructed of precision machined black-anodized aluminum, 2 set screws with a brass compression ring to sourly hold your diagonal.  

   This adapter is a great idea. thread your 2" filters in the MDA when you are using your 1.25' eyepieces, and swap out your eyepieces without having to unthread & rethread the filter back onto the eyepiece. Constructed of precision machined black-anodized aluminum, Brass Compression ring, 1 set screw, & a dust plug.

   This adapter is a great idea. thread your 2" filters in the MDA when you are using your 1.25' eyepieces, and swap out your eyepieces without having to unthread & rethread the filter back onto the eyepiece. Constructed of precision machined black-anodized aluminum, 1 set screw, &  a dust plug.

   The combination camera adapter will allow DSLR's & SLR's mounted with their T-Rings to securely attach to the adapter. The other end fits into a 1.25" focuser, or 2"-1.25" adapter. The one set screw (other side) will securely hold an EP inside the adapter for eyepiece projection photography. Remove the eyepiece and it's an extension tube for use with your camera. Constructed of precision machined black-anodized aluminum

   This adapter attaches your DSLR's, or SLR's T-Ring and allows you to image with 1.25" focusers.  Constructed of precision machined black-anodized aluminum. Threaded for 1.25" filters. 

   This adapter extends the focuser 56 mm or 2.24". It is used to bring some EP's to focus on low profile focusers.  Constructed of precision machined black-anodized aluminum, with nickel-chrome plated brass barrel, 1 set screw, and threading for 1.25" filters, and a captive set screw recess. Made in Canada

   This adapter will thread on to where your manufacturer supplied visual back is used on your 8 or 9.25" SCT. The SCT-1.25" Adapter w/ T-thread will allow you to directly attach your DSLR, or SLR to your SCT for prime focus astrophotography, as well as act as a 1.25" visual back. Constructed of precision machined black-anodized aluminum with 1 set screw.. Made in Japan 

   This adapter will thread on to where your manufacturer supplied visual back is used on your 8 or 9.25". The SCT-T-thread adapter 30 mm is a 2 piece adapter that allows you to rotate your camera to better frame your image. Constructed of precision machined black-anodized aluminum, threaded internally to reduce light scatter. Made in Canada

   This adapter will thread on to where your manufacturer supplied visual back is used on your 8 or 9.25". The SCT-T-thread adapter 55 mm is a 2 piece adapter that allows you to rotate your camera to better frame your image. which 25 mm more out focus than the TAS.  Constructed of precision machined black-anodized aluminum, threaded internally to reduce light scatter. Made in Canada

   The TE is an extension tube that will thread on to the TA, or your 1.25" visual back on your 8" or 9.25" SCT. Your DSLR, or SLR's T-ring threads onto it and you can increase image scale during eye piece projection astrophotography. Constructed of precision machined black-anodized aluminum, threaded internally to reduce light scatter. Made in Japan 

   A t-ring adapter is used to attach accessories securely to your DSLR, or SLR camera body. These are made in Japan, from Aluminum, & black anodized, 

 Available sizes

• 49mm to 43mm (49mm female thread to 43mm male thread).
• 49mm to 52mm (49mm female thread to 52mm male thread).
• 49mm to 55mm (49mm female thread to 55mm male thread).
• 49mm to 58mm (49mm female thread to 58mm male thread).