GFIs | Year of introduction | Tube diameter/material | Plate size/material | Resistance mechanism |
Molteno | 1979 | 0.63 mm OD 0.30 mm ID silicone | 135 mm2 polypropylene | None |
Baerveldt | 1990 | 0.63 mm OD 0.30 mm ID silicone | 200, 250, 350, 425, 500 mm2silicone | None |
Krupin with disc | 1990 | 0.58 mm OD 0.38 mm ID silicone | 180 mm2 silicone | Slit valve |
Ahmed | 1993 | 0.63 mm OD 0.30 mm ID silicone | 185 mm2 polypropylene with silicone valve | Venturi valve |
Optimed Model-1014 | 1995 | 0.56 mm OD 0.30 mm ID silicone | 140 mm2 silicone with PMMA matrix | Microtubules |
OD = outside diameter; ID = inside diameter.