Crescent wrenches for 6 sided schedule 40 bulkhead nuts. Short handles have a 20 degree offset. 10mm thick heavy duty ABS plastic are very sturdy for tightening the nuts.
3 sizes available.
1" bulkhead - with 53mm wrench opening
1.5" bulkhead - with 71mm wrench opening
2" bulkhead - with 87mm wrench opening