See Brady Products
Fir Tree Push-In Rivet - Nylon - 0.610 in (15.5 mm) Anchor Length - 0.236 in (6 mm) Compatible Hole Diameter - 0.091 to 0.350 in (2.3 to 8.9 mm) Compatible Panel Thickness Range - 0.701 in (17.8 mm) Head Diameter - 0.094 in (2.4 mm) Head Height - Black.