These policies combine a Public/Products Liability policy with a Professional Indemnity policy to protect against the potential uncertainties of which policy a claim should fall under.
A public/product liability policy provides cover for third party claims for property damage and personal injury where a Professional Indemnity policy provides cover for claims by third parties alleging financial loss due to a breach of your professional duty.
If the policies are placed separately and, particularly, if they are placed with different insurers, a claim could potentially fall in the grey area between the two policies.
It is preferable to insure these exposures under a policy which has been designed to specifically address this.
The policy provides coverage for claims arising from failure of your products, services and/or advice. Cover can also include infringement of intellectual property rights, defamation or breach of confidentiality, loss of documents/data and some policies can be extended to include defence costs for breach of contract.