Email Source: Spotler

Homepage: https://spotler.com/

This source is known to forward email

Capable of generating DMARC compliant email for others

Yes

Supports fully DMARC-compliant email.

Capable of signing email with DKIM for others

Yes

Contact Spotler support to configure DKIM.

Capable of sending SPF compliant email for others

Yes

Spotler provides the following include for your SPF - 'include:_spf.spotler.email'. In any case however, be sure to contact Spotler support in order to follow their setup procedure and understand how that setup works.