Shimano
Apologies, it's Shimano Bottom Bracket and I have a Shimano fit cheapo replacement, but it just seems to not be up to the job. Even when torqued down and threadlocked with a new crank bolt it still works loose. Never had a problem with square taper so my only conclusion is that it's the quality of the crank arm as i have already fitted a brand new UN54 bottom bracket. Cheers