HicarerAnchors for Concrete 1/4-20 Thread for Hurricane Shutter Concrete Anchors Hurricane Shutter Hardware Wall Anchor Bolts Machine Screw Bolts (50 Pcs)

I needed to mount some panels on a cement block wall and since I will need to take them off and put them back on repeatedly I wanted to use something threaded to hold the panels to the wall.This anchor is supposed to secure in place when the rear cone shaped threaded piece is pulled into the cylinder. The rear piece expands the cylinder into concrete as it is pulled into the cylinder.The problem with these pieces is that when I opened the bag about one third of them had the two pieces completely pushed together. How is the anchor going to expand into the wall if the rear piece is all the way in before putting them in the wall?From the pictures I attached, you can see that some of the two piece anchors are already pushed together. Some of these I could get to hold, but most would not and would turn in the hole as I screwed the bolt into them.So if you need these to hold something that can be installed and removed repeatedly, like plywood for hurricane preparation, make sure you have extras.