In response to the one other review - Monstrum Slim Profile Series Cantilever Offset Dual Ring Picatinny Scope Mount, 30mm

The weaver slot is smaller then a picatiny, so it makes absalutely no sense that a weaver mount would have less forward and back play! That being said the monstrum moint is a good mount if you upgrade the screws better screws are not expensive that being said .y monstrum mount quick release is so tight i have to use something to pry it open and its held up just fine i give it four stars because its not a top of the line mount but it has held zero never shifted and has worked well enough that i have not bothered upgrading it witch was my original plan just to see if i liked the offset amount