Three options available, first the low profile picatinny version to keep the block as close to the bottom of the stock as possible. Please note the low profile block is not quick release an allen key is needed, it uses two bolts to attach it to the rail after sliding it on.
Option two is the quick release picatinny option uses a picatinny clamp rather than a slot, it also uses thumbscrews to attach so no need for tools simply turn the screws to open the jaws of the clamp and it will release from the rail.
Option three is the quick release arca option uses an arca clamp, it also uses thumbscrews to attach so no need for tools simply turn the screws to open the jaws of the clamp and it will release from the rail.
Both blocks measure at 74mm x 74mm x 20mm adhering to the UK bench rest rules maximum width.
(We can make these to custom sizings/shape on request).
Will work with most picatinny/Arca rails, we recommend a picatinny rail at least 60mm long to get the best fit but can be used on any length of rail.