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Model	SV223	SV223	SV222	SV222	SV221	SV221	SV188/P	SV188/P
SKU	W9180A	W9180B	W9179A	W9179B	W9178A	W9178B	F9171A	F9171B	W2733A
Deflection Angle	90°	90°	45°	90°	90°	45°	90°	90°	90°
Diameter	1.25inch	2inch	1.25inch	1.25inch	1.25inch	1.25inch	1.25inch	1.25inch	2inch
Type	Mirror	Mirror	Prism	Prism	Mirror	Prism	Mirror	Mirror	Mirror
left and right imaging	reverse	reverse	forward	forward	reverse	forward	reverse	reverse	reverse
Up and down imaging	forward	forward	forward	forward	forward	forward	forward	forward	forward
Equivalent optical path (mm)	85.5	109.1/118.6	93	65.6	73	86	78.5	78.5
Effective aperture	25mm	43mm	16mm	19mm	29.5mm	19mm
Advantage	Coaxial locking, high-reflective dielectric coating, high surface accuracy	Coaxial locking, high reflective dielectric coating, high surface accuracy, dozens of layers of coating, high surface accuracy	Suitable for astronomical observations	Suitable for astronomical observations	Suitable for astronomical observations	Suitable for astronomical observations		Highly reflective dielectric coating

Features:

SV188P features sophisticated, Multi-layered dielectric coatings that provide an astounding 99% reflectivity for maximum view brightness and sharpness.
Dielectric mirror coatings are more durable and more reflective than enhanced aluminum coatings
Brass lock Screw for eyepiece or adapter and brass Compression rings features more precision and prevent barrels or the surface of eyepieces from marring and scratching.
1.25" nosepiece barrel is threaded to accept 1.25-Inch eyepiece and filters
Diagonal provides a comfortable 90-degree viewing orientation when observing the night sky through a refractor, Maksutov-Cassegrain (Mak-Cass) or Schmidt-Cassegrain telescope
Machined and anodized aluminum housing features machine-threaded baffles for optimized contrast
with a MAK scope you have much more back focus than a regular refractor scope and with a SCT & MAK it has lots of back focus.

Package Includes: