HD: A clank’s HD is equal to 3/4 of its engineer’s level.
BAB: A clank’s BAB is equal to its own HD.
Saves: All three of a clank’s saves are equal to half its HD.
Skills: A clank gets 4 skill points per HD.
Feats: A clank gets a feat at level 1, and then an additional feat every 2 HD.
Armor: A clank gains a bonus to natural armor, following the pattern on the Summoner’s Eidolon table.
Str/Dex: A clank gains a bonus to Str/Dex, following the pattern on the Summoner’s Eidolon table.
Design Pool: A clank has a design pool equal to an Eidolon’s evolution pool. This counts as having the Eidolon and it’s Evolution Pool class feature. Any feats, favored class bonuses, or items that increase an Eidolon or its evolution pool apply to the Clank and its design pool.
Max Attacks: A clank is limited in the number of attacks it can utilize, as listed on the Summoner’s Eidolon page.