OTC 6043 Blast-Vac Multipurpose Cleaning Gun

How do you use this to unclog a heater core without damaging it from the pressure?

I assume ":...one to a typical water faucet" is talking about a garden hose? Can Someone please verify how you hook this to a water source?

Is the item exact as pictured i.e. metal housing and brass trigger? Or is it an all plastic?

Whats the smallest size hose that will fit on it?