McLaren has become the second team to announce the date of the unveiling of its 2021 F1 car. It will showcase the new McLaren Mercedes on February 15, 2021 which is just a little over 2 weeks away. The car has been dubbed the MCL35M which is being called the successor to the MCL35 as due to the regulations thanks to the pandemic, teams aren't allowed to dramatically change their cars in the winter. That being said, the new MCL35M will likely be a major refresh as McLaren moves to Mercedes engines from the Renault ones it was using. This has changed the packaging of the car, apart from the changes brought about because of the new tyres by Pirelli and the aerodynamic changes thanks to the rules.
This will be the first McLaren car in 7 years to feature a Mercedes power train. In the mid-90s, Mercedes and McLaren had a fruitful partnership for almost two decades during which period the “Woking” based team won three world titles. In this period, the McLaren-Mercedes became the third most successful team in F1, taking on the likes of Ferrari, Renault and Red Bull.
— McLaren (@McLarenF1) January 28, 2021
The partnership came to an end in 2014 with the dawn of the hybrid era when former McLaren executive chairman deemed that the presence of the Mercedes works team meant that McLaren couldn't be competitive. He opted for Honda, harking back to the 80s and early 90s when the team was dominant with Honda engine package driven by Ayrton Senna and Alain Prost. This partnership was disastrous and it ended in 3 years which is when Mercedes opted for the Renault power unit.