I was on the Stena Mayo during her time in the Campos field, Brazil, until her return to the North Sea.
Quoting from her specifications :
CRANES One electro hydraulic offshore deck crane, make Normarine,
with tension contro! and telescopic whip line. Wire drum capacity:
Mix. lifting capacity: 60 tons at 10 m, 30 tons at 20 m.
Whip Line: 5 tons at24 m.
One electro hydraulic utility crane , make Normarine.
Max. lifting capacity: 5 tons at 10 m.
One 5 tons retractable crane boom arranged in side gate
opening SB. Outreach 3,0 m for ROV handling.