Best nail hardening product recommendations please

[Jemster]

After weeks of gel overlays I've managed to grow my nails to a decent length. I can't keep up the cost of the gel but my nails are paper thin underneath so will not survive long!
Can anyone recommend the best product for hardening nails as I really need this to have any chance of keeping them decent without the gel. Thanks

I've used the Sally Hanson range and my nails are far worse now. They were just weak to begin with, now they are weaker, splitting and peeling. Very annoyed as my hands look ugly.

Another vote for nailtiques
Nail envy just peeled off my nails

Phenomen oil by Jessica is the dogs bollox, it's fantastic stuff.

Jessica rejuvenation basecoat.

I have a Sensationail kit and wear this after I've had gel overlay on to make my nails less dry. It's completely brilliant.

Also have to second the Solar Oil but apparently almond oil works just as well!

Nailtiques number 2 worked better than OPI Nail Envy for me too.

I find keeping my nails varnished helps as wel. If they are not varnished they tend to split at the ends.