If you’ve been curious about at-home hair treatments from brands like Olaplex or K18, you may think you need to drop a pretty penny to restore your strands. While we love a worth-it splurge, what if we told you there’s a reader-loved, highly-rated, super versatile at-home treatment that only costs $7.50? Whether you’re dealing with hair thinning and fallout, chemical damage or changes from menopause or medications, the Cer-100 from the Korean brand Elizavecca is a super-nourishing Swiss army knife hair product that users love for repairing their manes. Reviewers say they use it as a regular post-shampoo conditioner, a hair mask and even as a leave-in conditioner, with some deeming the product the “best thing I’ve ever used on my hair” and “the only thing I use.” A consistently top-selling item here at Huffpost Shopping, the Cer-100 is an affordable at-home collagen protein treatment designed for all hair textures. Use it in the shower or apply it to dry ends. Or, enjoy it as a hair mask, applying it to clean, towel-dried hair for 5-20 minutes — you’ll likely see results fast. “This deep treatment conditioner works like magic for super thin hair,” one review said. “I had both dye damage and naturally fine strands, and this product made a noticeable difference after just one use. My hair immediately looked shinier, felt stronger and appeared fuller.”Loved by reviewers with self-described “lifeless old lady hair,” “post-chemo” hair that became “snarly and unmanageable,” decades of hair dye and damage or general frizz and flyaways, this stuff is potent treatment and “shower staple.” “I have a ton of super thin hair that feels stretchy, waxy, and tangles if you even look at it wrong. Normally I can’t run my fingers through it without ripping half of it out,” one user wrote. “I used this once and my hair actually feels like hair. Smooth, soft, no snagging, no stretching, no damage. I can run my fingers through it without getting stuck. One use. I’m seriously impressed.” Reviewers seem to love everything about the treatment — the clean smell, how it’s light and not greasy and how it doesn’t leave residue “like other conditioners.” Many note that after using it, their hair will stay shiny, soft and easier to style for days, if not a whole week. It’s also loved by users dealing with hair loss and breakage. “I have very brittle post-menopausal hair. It was breaking off so badly that my beautician only charged me half-price last time because there was so little hair to cut,” one wrote. “I have been using this every other day for 3 weeks now, and I am seeing a significant difference in the amount of hair in my comb and drain hair-catcher. Feels so soft and the frizziness has improved. I will be back to buy more.” “This needs 6 stars!” another review said. “My hair was dry and turning into straw, I used this ONCE and it looked fuller and it was unbelievably soft!!!” It comes in a travel-friendly size of 3.38 ounces, which users still deem “economical” and “an incredible value” as a little of the product goes a long way.Want to try the $8 hair product one reviewer called “the best hair treatment, mask and conditioner I’ve ever tried”? Check out more promising reviews of the Elizavecca cer-100 collagen treatment. “This is the best thing to happen to my hair, ever! I’m a post-menopausal women and my once beautiful, shiny, sleek and ultra-soft hair has become dry and brittle. I began noticing a change almost immediately upon using the CER-100 hair treatment. I feel like the hair I had in my 20′s has returned. My hair is so soft and I can actually run my fingers through it without get caught in the dry ends. I have also found that as time goes by, I am using this less often. I would 100 percent recommend this product to anyone dealing with dry brittle hair. It’s changed my life.” — Suzanne“I’ve tried tons of deep conditioners, but this one really stands out. My hair was feeling super dry and brittle from heat styling, and after just one use, I noticed a big difference. It’s thick and creamy, smells amazing (light and fresh), and rinses out without leaving any residue. I left it on for about 10-15 minutes, and my hair felt soft, silky, and way more manageable afterward. Even my split ends looked smoother. I’ve been using it once a week, and my hair honestly looks healthier and shinier than it has in months.” — Brenda“I am a ‘Recovering Hairdresser’ I did hair for years and used fantastic products! This by far is one of the best! My post menopause hair is thinning and dry. This product, makes it shine and feel extremely healthy! I color my hair and Elizavecca Cer-100 Collagen Coating Hair Protein Treatment, keeps it looking youthful and strong, no matter what I do. Blow dry, straighten, etc.” — jonna carlson“I normally don’t take the time to write reviews- especially if the product is what i expected. But this stuff? A miracle potion! My hair has been on the dry side since menopause started and I use Biolage products, but still feels like straw at times. I used this and it does what it says- my hair feels light and smooth , not one bit greasy, and like I just got a treatment at the salon . I can’t wait to see my hair stylist’s reaction next week when she sees the difference. Just get this stuff. For the price you have nothing to lose and everything to gain!” — Jules72“Obviously this product has great reviews, but I wasn’t sure HOW good it was. Y’all this saved my hair after one use. It’s quite literally liquid gold to me. I’m buying every product from this brand from now on. For reference my hair is bleached, platinum. It’s super thick and dry. It wasn’t to the point where I had bubble gum hair but it was starting to really lack in health especially when wet. I’m not even being dramatic after ONE use my hair feels like new, I’ve been using this for a week now and I’ve had growth, soft ness, and less frizz. GET IT.” — So cute!“I’ve been struggling with the changes in my hair. Old age (71) plus subjecting it to my new home’s humidity (FL) has taken an unexpected toll! I tried it today… My hair is softer and tangle free after my first use. Believe the reviews.. Well worth giving it a try!” — Roseann DEVASTO“My colored curls were feeling dry, limp, and a little lifeless — until I tried this protein treatment! It gave my hair the strength and bounce it was seriously missing. After just one use, I could feel the difference: less breakage, more definition, and that soft-but-strong feeling I hadn’t had in a while.” — Chelsea B