Topper clamps- is there something better?

I have this type and am finding that my topper shifts backwards over time.

https://www.aaproductsinc.com/colle...of-4-black-p-ac4-04-blk?variant=7669470330946

My topper is a Leer contractor top on a 6.5' bed.

I'm trying to decide if I should just add another pair of clamps, or if there is something better than these for a good snug fit.

Are ya'll using the same type?

 

can you add some rubber strips on top of the bedrail to create some grip? maybe

 

I have a soft top and use these type of clamps. Shouldn't your topper have a rubber seal between the bed and bottom of topper? Are the clamps tight enough?
You can always add more clamps to make sure it stays put.

 

Home depot sells a waterproof weatherstripping sticky on one side. It is 1”” thick but squishes down to create a tight seal if there is impurities in the fibreglass.

 

The weatherstrip that was under it from the install worked its way out. It's the 1/4" x 2" stuff. I bought some better rubber seal to replace it. It wasn't cheap, so I want to be sure the shell doesn't shift afterwards.

 

Those are the industry standard clamp design.

If it is sliding, then you do not have enough friction. Put a seal under the rails, and/or rough up the top surface under the clamp. Also check the tension bolts every now and then to make sure they have not loosened.

If you want a mechanical stop, then drill and countersink for 8-32 x 3/8" flat head screws, with the head under the rail and a lock nut on top and then butt the clamp against the nut.

 

Looking again, you might be better off with Softopper's clamp. It has a longer support surface for the top portion of the clamp than the Leer clamp.

If you add a set of these to your current set, then you should not have any problem. Or, I would use two sets (four on each side) of these if you want to be consistent.

https://www.softopper.com/accessories-parts/replacement-parts/steel-bedrail-softopper-utility-clamps