The G4 bulbs on my dining room light have 0.7mm thick pins. I bought these halogen bulbs from Simba Lighting and most bulbs have 0.8mm to 0.83mm pins. There were four lamps from two boxes of 10 each measuring 0.7mm. I bought a branded T3, G4 base halogen bulb for landscape lighting and it had 0.7mm pins. So I think these bulbs are out of spec. Please see the attached photo which shows the dimensions of the standard G4 and these lamps with calipers.