HydrofarmHGCOV4 Rockwool Block Cover (40 Pack), 4"

They still curl but at least they aren’t made in China. Will buy again.

How the REAL Hydrofarm (inc) is not suing this company is UNREAL... The covers are a total JOKE.. they are as thin as super cheap panda film (like a white kitchen trash bag thin). I just got them, (laughed) and then put them on some rock wool cubes and they're all flowing up at the tips from the green house fan so its going to be a Six Flags Theme park for algae to form at the corners and grow everywhere on top of the cubes. They are basically buying the cheapest thinnest black/white panda film the can find and then somehow cutting them into grow cube sizes, stomping a hole in the middle of them and then printing out fake hydrofarm labels and throwing the entire pile of horse manure into a ziplock bag made to look like real, actual hydrofarm covers/product. DO NOT BUY! If you want ones this bad, just buy 100 feet of trash ultra-thin black/white panda film for $40 and cut 5,000 of them out for yourself.

I'm using small rock wool cubes & I have to cut these down which is a total pain. Then they are never just right & move around alot. I wish they would offer a size to fit the rock wool cubes for aeroponic growers. I own a tower garden & have yet to find one that fits. Actually they are the ones that should offer one! Otherwise they do the trick (if they stay put & don't move). I gave a 3 star because of it not working for my individual needs. Maybe they'll see this & manufacturer one for tower garden owners! ...or maybe I should.

I recieved groxpress not Hydrofarm. Anyone who has purchased these products knows groxpress is a cheap knock off.Buy Hydrofarm if you want them to last. Awaiting return request. One other thing the one I recieved was torn on one side not cut. Like I said a cheap copy. I will update when I get my refund.

quality material used. DO NOT CURL UP like the cheaper knockoff.

I have all my plants in 4-inch rockwool cubes set into Hydroton in a hydroponic flood tray, and was constantly plagued with powdery mildew and algae. These covers eliminate the problem by preventing light from reaching the vulnerable surface. Cheap and effective, great product!

There's not a lot to say about this. It works exactly as advertised. It fits well and prevents algae growth.

Great product easier to buy than make myself. Re useable, I just stick in dishwasher to sanitize.

You can buy 10x25ft panda film the real stuff for 30$ ish and make about 40,000 of these for about 2-3x the cost of 40... but I guess if your lazy or only will ever use 40 for a hobbiest to save time / have a life time supply for 10$ is not and no but it is what it is and it’s just knock off thin pre cut 4inch squares of Mylar film black and white !Sorry wish these where cube caps 4inch reusable like it says / looks in photo... a little deceiving and first 40 orders whee stolen by the purolator Guy (faked my siganture) so apprentlyntheyre worth his job ... so I guess to some there quite valuable ;p ahah probably not a good joke but at this point all I can do is chuckle .. since legalization all garden supply’s and fans stents in this site agvengone yo 10-500% in price .. it’s insane some stuff I When gotten 10s of times for 4-7$ is joe 67$’each!! Like what??Read he discription and product info carefully !! READ PRODUCt INFo BeFoRE BuyiNg (NOT cube caps!) just Mylar !

This is the biggest rip off this is actually black and white plastic that you can buy for the hydroponic store for a dollar a foot I paid $30 for 40 squares I thought they were hard plastic squares again buyer beware you got me this time

arrived fast, are as described. One side is black and one side is white, I use the white side to reflect the light onto my plants. they are over rockwool and so far I see no mold on any of the rockwool with this on

Exactly as expected. Black and white one opposing sides

Does what it is supposed to do.