The drain line must not sag below the point where it connects to the main drain. If it does, the symptom will be that some water will drain on top of your counter from the overflow hole on the faucet. That's why they talk about making it "as straight as possible".
I tested it - yes, a 3/8 drill bit will work but it's pretty tight. To make it easier, insert the drain line into the drain clamp housing and 1/4" thru. Then wiggle the end of the drain line into the 3/8 hole in the drain pipe with the housing already on the black drain line. Then attach the back clamp half with screws.
Odd that the feed line is 1/4 the other lines are 3/8. Wouldn't you want the water feed line also 3/8. I don't plan on installing under the sink probably make the feed line also 3/8 I'll be installing in my garage. Video is nice but be better if you include a good installation book page through as you install it.
STAY AWAY form fresh water systems! Shop around for a better company with better return and broken and/or before it leaves their warehouse policy. DONT NOT deal with the NOE PURE crap shown here, it is a generic looking and has a weak mounting bracket leaving the filters in a sagging position. the plastic snap thingys do not hold the filters in the place tightly. mine came plumbed wrong, and the pump installed upside down, when i got it hooked up the pump actually leaks internally. NOW, i am dealing with fresh water systems CRAPY return and warranty process instead of them just sending me a new pump. 3 weeks after the purchase of this POS i am still BUYING bottled water. the water in my neighborhood is barely potable....THANKS FRESH WATER SYSTEMS! for nothing...wait, you did get about $450.00 from me. i wonder how much i will get back? that could have bought 180 gallons of drinking water. so many other players in the drinking water business. just sayin...
