SmallRig QR Pack (Manfrotto) 1503 includes a Quick Release Adapter & a Sliding Plate.
Compatible with the 501PL camera plated (supplied with the head 501HDV, 503 and 519 Video Heads) and special 501PLONG accessory plate.
This Quick Release Adapter gives you the freedom to remove the camera from the head without detaching it from the plate and put it on any other support.
The sliding plate included is of Manfrotto 501PL standard.
A 1/4"-20 screw and a 3/8"-16 screw are included so you can use the plate with various cameras.
Click here to see more details.