"Holding down post support to concrete. Would like to have seen flared in top for hammering into hole without damaging thread but used a spare nut to take the hammer blows. Drilled with SDS to exact size on packet but still needed a little widening to take bolt using large hammer. Once in they were fine but took a little fettling to get four of them to line up enough to take holes in post support. Next time don't just mark the holes but drill one, insert anchor, bolt down support and drill the next one through the post support and fit. Takes more time but no need to persuade bolt heads to line up with holes in base."