"Is it compact?" LOL! These questions in the review page are a riot!! Yes, the coils are very compact, lolol!
Anyway, installed both in a Kohler CH18S powering an early 90's Cub Cadet 1864 - quite a bit of labor to reach these in a horizontal shaft engine. Engine had to be unbolted, along with driveshaft, then engine spun 90° to remove rear cover. Mouse chewed through the nearly 30 year old OE spark plug wire - coil would still work otherwise! Changed both due to labor involved. Gigantic mouse nest found back there, and also many bare wires, so we killed 3 birds with one stone - fixed the dead miss, prevented engine meltdown, and prevented future misfiring events due to bare kill wires grounding out. Engine started right up when finished, and blades were now able to reach their designed RPM. Much better off with OE parts rather than the cheap Chinese stuff all over eBay. Way too much labor here to try and save a buck on parts. Do it right, do it ONCE!