We do not recommend travelling without the child car seat .Its at your descretion and we accept no liability for any person injury .

However the below is stated on the government website 

Taxis and minicabs (private hire vehicles)

If the driver doesn’t provide the correct child car seat, children can travel without one – but only if they travel on a rear seat:

• and wear an adult seat belt if they’re 3 or older
• without a seat belt if they’re under 3

Source :-
https://www.gov.uk/child-car-seats-the-rules/when-a-child-can-travel-without-a-car-seat#:~:text=Taxis and minicabs (private hire,if they’re under 3We have a few Different Variants of Child Seats

We have the following Child Sears available and you are also encouraged to use and bring your own for your Trips .

Seat 1 – Isofix Recaro Monza -Group 2 and 3 SPEC for a child 15-36kg in weight ( Has Built in Speakers and a 3.5mm AUX cable jack so the child can listen to audio )