No. BlackBerry KEY2 does not have any specific water protection certification.
Yes, BlackBerry KEY2 does support wi-fi calling.
Yes, BlackBerry KEY2 can record 4k videos at 30fps.
Yes, BlackBerry KEY2 is VoLTE enabled mobile phone.
BlackBerry KEY2 is available in 2 variants - Single sim and Dual Sim. The model available on OnlyMobiles.com is a dual sim variant. It has a hybrid sim slot. You can use either 2 sim cards or 1 sim card and a memory card.
Stellar battery life. A tactile and genuinely useful keyboard. Great software with a focus on security and privacy. What more could you want? The BlackBerry Key2 is an exceptional phone.
The BlackBerry KEY2 is the best Android-powered BlackBerry ever made, and it improves on last year's formula in almost every way.