T3 JC halogen capsules at 10W and 20W on a G4 bi-pin base running 12V, delivering 105 and 260 lumens, in singles and two-packs.
G4 pin spacing is 4 mm and will not seat in a G9 or GY6.35 fixture despite the lamps looking near-identical in the pack. Pin type and voltage are stated on every SKU for that reason.
Small capsules feed under-cabinet fittings, display lighting and decorative chandeliers. The larger capsule is T4 JC, and the LED replacement is in LED G4, G9 & B6.