Child booster seats do not fit in front seats

[kpm278]

Hi

Tried search but no joy.

I have a couple of different booster seats but they don't fit in the s-line front seats, they are too wide for the seat bolsters and end up at quite an angle. I've used towels under the booster seat a couple of times but I don't think this is safe, in a front collision the towels could come out and suddenly the seatbelt isn't tight.

Is there a clever method to raise the booster seat, or narrower booster seats that fit?

Thanks, Kris