I like the looks of those. But not the cost. Might be a good option though if standard 3M electrical tape won't cover the muzzle brake. If I buy one roll of 3M tape, I can cover my barrel many times. Much more than the 6 units supplied in this package of muzzle covers.
I carry a used roll of 3M tape in my pack, so I don't carry the weight of a full roll, for purposes of replacement out in the field.
But here's a tip for those using electrical tape. After the first two strips are used to criss-cross the muzzle and brake, the third piece I use to strap the four loose ends securely to the barrel is left long enough so that I can unravel it after shooting, and re-use it to criss-cross cover the muzzle bore and brake again, until I get back to my backpack or camp in order to get some more tape. That way, even if I carry no additional tape with me, I can shoot the rifle at game once, and still have the third strip for reuse, since the third strip is behind the brake so it's never damaged by the muzzle blast. Unravel the third strip, tear it in half, and then criss-cross over the muzzle. Good to go again!
I've mentioned the 3M tape here several times because it remains sticky enough to cover my brakes and muzzle - even without the use of the third strap wrapped around the barrel behind the brake. Some of the discount electrical tape I've tried tends to come loose.
But I use to the third strap so I can recover my muzzle brake, after I've fired on the target animal.