The original LAVIS builder in a bottle is thinner and is shaped by turning the hand so the gel settles into a curve. Builder Gel 2 is thicker, closer to a rubber base, and holds its shape without flipping the hand. B1 and B2 are the builder in a bottle collections that LAVIS lists as both HEMA-free and TPO-free.
LAVIS lists its builder gel range as HEMA-free, and B1 and B2 are also listed as TPO-free. HEMA-free is not the same as allergy-free, because other acrylates can still cause reactions, so a patch test is wise for clients with a history of sensitivity. Keep builder off the skin and cuticle during application.
Builder layers are thicker than colour coats, so lamp power matters. Use a lamp of at least 24 watts, and a 48 watt or stronger lamp is the better choice for builder work. Cure each layer for the time the label gives for your lamp, and make sure the whole nail sits inside the lamp. A weak lamp can leave the inside of a thick layer under-cured even when the surface feels hard.
The bottle kits bundle several builder shades with a base and a top in 15 ml bottles. Kit 6, for example, lists four shades with base and top, and Master Kit 5 adds a dual form for extensions. Read each kit title for its exact shade numbers and contents before you order, and check stock on the listing. Builder shades are also sold as single bottles.
Yes. A builder overlay can be filed down and rebalanced with fresh builder at the next visit instead of being soaked off every time. File away the grown-out edge and any lifted areas, prep the exposed nail, then rebuild the apex with thin layers and cure each one fully before you finish. Finish with a top coat over the rebuilt overlay.