These are now called "premium bagging blades" on the package. Sears should change the description. I have an older 16HP 42" lawn tractor which came with the mulching blades. I've tried several premium and standard mulching and all-purpose blades in the past with and without a 2-bin hard bagger. These perform exceptionally well overall and outperform even the most expensive mulching+bagging blades for bagging. Thick 1 to 2 inch clippings blew straight into the bagger, unlike the mulching+bagging blades which clogged every 3-4 feet. It even managed to bag pine stump grindings and small sticks in sparing amounts. Some clogging did occur, but it was mostly due to fast mower speed and damp clippings. A few shakes of the feed tube cleared up clogs. If you have slow growth grass or if you mow often then you will have absolutely no problems with a bagger and these blades. I highly recommend them also for leaf and bloom bagging. I've read complaints on lawncare forums where only the far left bin filled up due to a loss of vacuum. I only experienced a small loss in vacuum after the left bin filled. In most case, all bins filled completely all the way to the top of the cover. Be weary of soggy grass in general. No blade can easily discharge wet grass, much less cleanly blow it through a bagging tube. I've tried premium "no-clog" or "no-stick" blades and even those clogged with an open side-discharge.
Thought I was ordering 2 blades for my twin blade mower. Received 1 blade.
This is 1 blade 21" long. Not a package of 2 making a total length of 42". The description here doesn't make that clear.. Someone had even asked here to clear this up and was told by it appears a sears employee that it was 2 blades. Well, I can confirm it's only 1 blade. I ordered it and that is what they tried to give me. I talked with their manager and even after shown him the online information all he would do is let me return them. And that took over 30 minutes!!! I'm sure the blade is fine thus I gave it 2 stars but I can certainly get it cheaper elsewhere. If I was rating this site and sears today it'd be 0 stars.
I bought three sets of Craftsman 24652 42" tractor Blades ... when I installed the first pair they were a matched pair and made the tractor hum as it tossed the clippings half way across the yard. They are much heavier than the "brand X" ones I had been getting from Lowes down the street and that heavy duty label was what attracted me in the first place. Anyway, they are a great product with good engineering and manufacture and these are the blades I should have always been using.