Does HQI= double ended or are there screw HQI bulbs?

[eaglet]

Does HQI= double ended or are there screw HQI bulbs? If there are screw type what is the diffrence between the 2. What is the diff between HQI and mongul. Thanks I am confused Stan

 

[pathos]

double-ended

 

[golfish]

HQI's
150 watt double ended
250 watt double ended and single ended
400 watt single ended
The double ended bulbs must be used in some kind of pendant with a UV shield. Some 250 watt single ended\mogul base bulbs can only run on an HQI ballast. Some(German) can run on both an HQI and MH ballast, these will burn brighter on an HQI ballast.

I bet your real confused now

Mark