L1, L2 cross-references to TIP and RING respectively per standard US phone nomenclature. TX/TS can be wired as the second line TIP2/TX, RING2/TS or a sort of daisy chain, but in a single line system, can be ignored.

Wiring on this will be
- Green => Tip => L1
- Red => Ring => L2
This pair will connect to the center pair of contacts in the modular socket/jack. Most phone wall cords sold are RJ-11 with a single pair to save money.
What the phone company has given you is a standard T-568A (Cat 4 or 5) color coded single pair. If you examine it closely, one wire's insulation will be white with blue stripe and the other will be solid blue.
It cross-references to the old RING/L1, TIP/L2 wiring convention as follows:
- White/Blue => Green => Tip => L1
- Blue => Red => Ring => L2
RJ Modular wiring:
- RJ-11 Single Pair
- RJ-14 Two Pair
- RJ-25 Three Pair
POTS Local Loop voltages (positive ground to reduce electrolytic corrosion):
- Tip is at ground potential
- Ring is -48V DC (nominal)