The S6 uses the square threaded tube.
The W5050SQ3 is also a nice throwy emitter option for the S6 but it doesn’t come in 5000K like the SFT40.
The SFT40 in this post is the 6000K version:
The S6 uses the square threaded tube.
The W5050SQ3 is also a nice throwy emitter option for the S6 but it doesn’t come in 5000K like the SFT40.
The SFT40 in this post is the 6000K version: