SPACI score report for 1a6n in ASTRAL 2.05:

PDB Entry: 1a6n
SPACI score: 0.92
AEROSPACI score: 0.92

Experiment type: XRAY
Resolution: 1.15
R-factor: 0.122
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 1
PCK3 PROCHECK H-bonds: 1
WCK1 WHAT_CHECK Packing: 0.035
WCK2 WHAT_CHECK Ramachandran: 1.192
WCK3 WHAT_CHECK Chi angles: 0.055
WCK4 WHAT_CHECK Backbone: 1.55

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).