Parts Breakdown:

Figure #	McMaster-Carr #	Description	Price
1	51835 K272	3/8” compression tube sleeve for 3/8” OD must be drilled & tapped to accept figure #4 (optional)	1-9 $1.03 10+ $.79
2	5478 K111	¼” NPT Male shut off valve tube coupling	1-4 $14.11 5+ $11.55
3	5478 K71	¼” quick connect tube coupling ¼” socket	1-4 $14.52 5+ $11.88
4	8063 K33	Brass air tank valve 1/8” NPT 15/16” overall length (optional)	1-4 $2.34 5+ $1.82
5	55495 K13	DOT Nylon II tubing .251 ID x 3/8” OD x .62 wall	1-249ft $.79 250+ft $.64
6	51835 K292	3/8” compress tube fit for nylon tube nut or you can re-use nut from existing fitting	1-9 $3.40 10+ $2.59
7	51835 K282	3/8” compress tube sleeve for 3/8” OD do not re-use existing sleeve	1-9 $1.03 10+ $.79

Socket & Plug

These sockets & plugs have an acetal valve and Buna-N O-ring. I have not examined the factory components for comparison. My total cost to assemble ten (10 complete lines =approx $250.00 you will save 15-20% when ordering five or more fittings from McMaster Carr.