What type of connector do I need?

I'm having a tough time understanding what type of connector I need to hook my compressor to the sprinkler system. Here is a picture of where I need to connect. Any help would be greatly appreciated.

connector

You need an adapter that fits that socket, usually it will be a hose valve adapter. You will have to determine the make and model, then contact a supplier of that line to see if they have something other than an irrigation head which will go into that device. once you have the adapter, THEN you can get whatever it takes to convert it to your air hose.

What you have there is a quick coupler valve connection. You will need to contact a irrigation supply house and purchase a brass quick coupler key. You will have to give them the brand and model #, which should be on the plastic cover. It appears to be a double lug QCV. " It also appears to be a 3/4" size. Keys are pretty standard, so another brand will probably fit. The key is inserted into the coupler and turned a half turn which opens a spring loaded check valve. You can then blow air thru it. As mentioned in the first reply, you will have to make up your own adapters to fit the key and your air hose connection.

Okay. Thanks for your help.