Spectral profiles designed after UV, B, V, Rc, Ic Johnson/Cousins
  Improved B filter (B***) extending blocking >1100 nm and eliminating small light leaks that affected measurements of reddest stars in our initial filters
  100% coated – no colored glass
  Peak transmission guaranteed > 90%
  <0.01%T(ave) typical out-of-band 300 – 1100 nm; additionally =<0.1% Tabs for B***
  Striae-free, single fused silica substrates
  1/4-wave propagated wavefront prior to coating
  <0.5 arcminute substrate parallelism
  3.000 +/-0.025 mm substrate thickness
  Parfocal with all Astrodon filters
  Edge-blackened
  1.25″ mounted, 49.7 mm dia. and square unmounted
  Other sizes available on a custom basis for filters as large as 150 mm
  Proudly made in the U.S.A.