Beware. This topic may be a possible FAQ, and will likely become a heated discussion. Please try to keep a level head, use RAW, provide references, citation and other binding/official sources, and follow the Community Guidelines at all times.
'Inhales a deep breath'
Klars counts as light shield for the purpose of using it as a shield. We know this because of this FAQ, and it it written least 2 times in the Ultimate Equipment, page 12 and 31.
My questions,
1)Can I shield bash with a Klar?
If no, question 2 and 3 are irrelevant. Question 4 must be addressed.
If yes, please address question 2 and 3. Question 4 is irrelevant.
2)If I can shield bash with a Klar, would I be using light spiked shield damage and "hand of effort"?
3)If Klars are one handed weapon, supported by the weapon table in Ultimate Equipment on page 18, then what would happen if I got a large Klar? Would it become an inappropriately sized two handed Weapon and still count as an inappropriately sized light shield for damage and "hand of effort"?
4)If I can't shield bash with a Klar. Would certain feats, like Improved shield bash, and special shield ability, like bashing, become useless for the Klar?
"Hand of effort" is a much argued over unwritten rule in Pathfinder. Often used to explain why one can not two-weapon fight while using a two-handed weapon.
So if you do not want anything to do with "Hand of effort", You may want to avoid this tread.
I posted this tread in General Discussion, so I may refine my question if I should ever post it on Rules/Question.