Which Bristell models can tow gliders?

“Five models have an approved glider capacity — the Bristell Classic 912iS (gliders up to 700 kg / 1,543 lbs), Classic 915iS (up to 800 kg / 1,764 lbs), Classic 916iS (up to 850 kg / 1,874 lbs), Bristell B23-915iS (up to 800 kg / 1,764 lbs) and Bristell B23-916iS (up to 850 kg / 1,874 lbs).”