SPACI score report for 3nfc in ASTRAL 2.06:

PDB Entry: 3nfc
SPACI score: 0.36
AEROSPACI score: 0.36

Experiment type: XRAY
Resolution: 2
R-factor: 0.251
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 3
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.363
WCK2 WHAT_CHECK Ramachandran: -1.145
WCK3 WHAT_CHECK Chi angles: -2.018
WCK4 WHAT_CHECK Backbone: 3.535

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).