SPACI score report for 1a6t in ASTRAL 1.69:

PDB Entry: 1a6t
SPACI score: 0.31
AEROSPACI score: 0.31

Experiment type: XRAY
Resolution: 2.7
R-factor: 0.169
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: 1.086
WCK2 WHAT_CHECK Ramachandran: -1.877
WCK3 WHAT_CHECK Chi angles: -2.557
WCK4 WHAT_CHECK Backbone: -5.698

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).