The Really Right Stuff MPRS 40mm Sliding Rail with L-Platefrom Really Right Stuff MPRS 40mm Sliding Rail with L-Plateis designed for the Canon 800mm and 600mm f/11 prime lenses. These lightweight, extendable lenses makes proper balancing difficult; the MPRS-40 solves that problem by allowing the foot to slide back to the balance point when the lenses are extended for use, and forward when in the stowed position. Since the lenses lack a collar, holes are provided for mounting the L-plate to the foot, allowing quick and easy vertical orientation.

40mm of Sliding Travel    Thumbscrew for Quick Adjustment    Laser Markings for Repeatable Placement    QD Socket    3/8"-16 Thread    1/4"-20 Threads for L-Plate    6061 Aluminum

Related Questions and Answers

Q: 1. Will this work with the QD strap swivel--is there a qd socket?

A: There is no QD socket on the Really Right Stuff 4.4" Multi-Purpose Rail (1/4"-20).

Q: 2. Does it work for Canon EF 100-400 mm lens?

A: Yes, the Really Right Stuff 6" Multi-Purpose Rail (1/4"-20) is compatible with the Canon EF 100-400mm f/4.5-5.6L IS II USM Lens.

Q: 3. How is camera twist prevented when using this product? The anti-twist feature does not work.

A: This is meant to be used with RRS plates with the lip to prevent any sort of lens twist. On a larger lens foot with two 1/4'-20 screw holes, you can put in both screws to prevent twist.

Q: 4. Will this work with RRS L brackets?

A: Yes, the Really Right Stuff DJI Ronin S2 CL Rail is compatible with the Really Right Stuff L brackets.

Q: 5. For Olympus lens 40-150mm whch size fits- the 1/4-20 or the 3/8-16?

A: You need the 1/4-20" for the 40-150mm pro lens.

Q: 6. The item pictured is the older, discontinued version of the 192mm / 7.6 Multi-Purpose Rail. Is this the older version pictured? Or is the picture inaccurate and this is the new, updated version?

A: This item is the currently available, latest version, of Really Right Stuff's 192mm rail (7.6 ). It is not discontinued and still sold via their site and ours.

Q: 7. Is this plate compatible with the Manfrotto 504PLONG? I have a Manfrotto MVH502AH video head and would like to be sure I can use it on that head. Thank you

A: Yes and no. the RS2 (and by extension this Really Right stuff substitute) is compatible with with Manfrotto tripod heads but it is more difficult to use than normal Manfrotto plates. It mounts from front to back instead of back to front. The fact that it mounts in the opposite direction makes it awkward to get the quick release plate on and off your tripod. the safety mechanism can get caught leaving your camera stuck on the tripod and requiring force to remove it. Yes the plate will mount on your tripod but it will be more difficult to get it on and off your tripod than a normal manfrotto quick release plate.

Q: 8. Will this fit using two screws to the foot of the AF-S NIKKOR 500mm f/5.6E PF ED VR lens? I estimate the two threaded holes in the lens foot to be on 30mm centers.

A: The Really Right Stuff 2.9" Multi-Purpose Rail (1/4"-20) will fit the AF-S NIKKOR 500mm f/5.6E PF ED VR lens using both screws.

Q: 9. Is there a QD socket on the rail?

A: No theReally Right Stuff 4.4" Multi-Purpose Rail (1/4"-20) BH #REMPR113RAIL • MFR #MPR-113 RAIL does not have a QD socket.

Q: 10. Is this rail compatible with Arca-Swiss accessories (can it replace multi-purpose rails, like the MPR-270)?

A: The Really Right Stuff Multipurpose Cinema Rail is Arca Swiss compatible. Yes, It could replace MPR-270.