That is why never to go under a car on a trolley jack - was just placing the axel stands under when that gave....
it showed no signs of damage before hand and was being used correctly on the jacking point of a vehicle well under the weight limit.
you wont go wrong with that sealey , you will how ever find its bigger and heavier than you think - that is good though , longer wider base is more stable.
i ended up with an Arcan 2t (american t) - so about 1.8 Real t its aluminium , its also huge - low profile and has a quick and high lift - its a similar weight to the one above but about twice as long and wide much more stable and means i no longer need to use my bottle jack on my 4x4s. - but its about 108 quid.