SV503 Refractor Telescope: An ED glass refractor with a built-in field flattener and dual-speed focuser for exceptionally sharp, color-accurate, and vibration-free views. SV165 Mini Guide Scope: A compact guide scope with sharp, wide-field optics and wide compatibility for easy and precise auto-guiding with mainstream cameras. SV211 Dovetail Base: Features a convenient carry handle and universal dovetail base for easy, safe transport and mounting of guide scopes and accessories. Universal Dovetail Base: A durable, lightweight universal base for securely adding a second or third finder scope or reflex sight to any telescope tube. 1.25" UV IR Cut Block Filter: This true optical quality filter blocks UV/IR light to protect your lens and deliver high-contrast, sharp images with natural colors.