Rain Bird MUF-SPK4S Drip Irrigation Micro-Umbrella Bubbler on Stake, 360 Full Circle Pattern, 0-3' Spray Distance, 4-Pack

Do they allow the use in line (in/out) or do I need tees hose connectors ?

the 2 ends of the barbed connector that comes with each bubbler are slightly different. does it matter which end I insert into the 1/4" line?

Max diameter answers range from 4" to 5' (6' in mfg description) - why?

What is the GPH on this?