Perhaps his version is clearer than the traditional TULIP.

• Humanity’s radical corruption (T: Total depravity)
• God’s sovereign choice (U: Unconditional election)
• Christ’s purposeful atonement (L: Limited atonement)
• The Spirit’s effective call (I: Irresistible grace)
• God’s preservation of the saints (P: Perseverance of the saints)

What is Reformed Theology?, p.138

(GSiV: TULIP: Possible translations in Vietnamese; Election; Atonement; Piper; Eternal security; Salvation; Evangelism and Calvinism; TULIP)