Where to buy strong chains

Where would I buy really strong chains or any other alternative suggestions on best type of material to chain 2 bikes onto a pillar in an underground garage. The garage is private but it is all open parking spaces. Unfortunately we have had 2 lots stolen when people visiting didn't put the bikes back the way they found them.

Bee

Leroy Merlin sell chains of all strengths...They will cut the length you require..

Search for “Sold Secure” products on Amazon. These security products are insurance industry recognised

Many thanks. Unfortunately I don't have time to order from Amazon but they sound good.

Bee

Make sure you get a really thick strong padlock as that's what they will cut/break

Go to a motorcycle shop and buy proper security chains.

Josephine's ferreteria have chains of all thicknesses and they will cut to any length you require. the shop is just on the right 100 yards past the arches

You need a high tensile cable lock, unless you get a chain that needs a electric angle grinder to cut.Bolt cutters and hacksaw will cut and remove cheaper options.

Motor bike shop best bet

Saw some motorbike chains with lock in Lidls this morning. €20. About 2 feet long