Mast climbing solo

Midsommar night was very calm in the harbour. Almost noone in proximity so we had calm and easy job to guard the boats. Thanks to Albert night guarding of our club's marina went quickly and I did not fall asleep. 
Started at 21:00 we ended at 5:00 am after some grilling, talking and setting up HAM radio in the middle of "night" - no real night thou as it really does not become dark at this time of year here.
At 5 am I climbed solo onto my mast to fix lost HW on one of "Motoko" spridare. I used very simple yet safe setup: 3 small Prussic knots which held my ass safely 7 meters above the deck. 
It was first time for me to use them but they work smoothly! 
No need to invest in pricy climbing equipment!