Seymour Solar makes the finest, yet most-affordable solar filters we’ve ever tested- starting at just $85/pair. Their Helios thin-film has a consistent yellow-orange solar image, with higher contrast than competitor’s filters. For binoculars capable of magnifications greater than 25x, we also offer Seymour Premium Glass filters, for highest-possible resolution. The glass filters are recommended when doing photography using a Novagrade Smartphone or Tablet Adapter. For visual observation, the Helios film filters are all you need. For the BT-100-45, there is a third smaller film filter to for the the 7×50 finder-scope. All filters meet ISO 123112-2 requirements. No returns accepted for solar filters.