A "LP4-3 rivet" is typically a type of blind rivet, often referred to as a "Gesipa GSMD41-43APG PolyGrip rivet," which is used in construction and manufacturing applications where access is only available from one side of the materials being joined; the "LP4-3" designation likely indicates a specific size and grip range for this type of rivet
Zenair Blind Rivets These rivets are corrosion resistant, and the stem becomes locked in after being set. Also, not many different lengths are required for different diameters or thicknesses.
For any of these - check the strength and materials to ensure compatibility.
Also, if it's an RV-12 (-12iS) that it's going on, there are specific rules for where your parts come from. I think those are limited to Van's parts, unless it's not going to be E-LSA.
Also, if it's an RV-12 (-12iS) that it's going on, there are specific rules for where your parts come from. I think those are limited to Van's parts, unless it's not going to be E-LSA.
This is true, but only during initial construction before the airworthiness cert is issued. After that, anything goes, just like any other experimental.