It's fine but not really worth the price - OpticsPlanet Exclusive Swampfox Sentinel 1x16mm Ultra Compact Micro Red Dot Sight

This Micro dot is fine but there are others with similar features at a lower cost.

Full disclosure, I'm a newbie when it comes to red dots of any type. This red dot is mounted on a Ruger 57 and it fits fine. Once it was zeroed in, it works fine. The dot brightness and size is a bit more than just adequate (in other words, it is fine). The site picture is fine but I wish it was a bit larger (but then again is this a ultra compact micro dot).

One thing I really don't like are the elevation and windage adjustment screws. They are very small and have a single slot (not phillips). Finding the slot with the supplied tool is a real bugger. They really should be a phillps or torx type screw. I will heading to the hardware store to purchase a slotted screw driver that fits these tiny screws and with a much larger handle so that adjusting the elevation and windage is an easier proposition.

Over all it is an OK red dot, I just believe it is a bit high priced for what you receive.