Philippine Civil Code, Art. 1502

When goods are delivered to the buyer "on sale or return" to give the buyer an option to return the goods instead of paying the price, the ownership passes to the buyer on delivery, but he may revest the ownership in the seller by returning or tendering the goods within the time fixed in the contract, or, if no time has been fixed, within a reasonable time. (n) When goods are delivered to the buyer on approval or on trial or on satisfaction, or other similar terms, the ownership therein passes to the buyer: (1) When he signifies his approval or acceptance to the seller or does any other act adopting the transaction; (2) If he does not signify his approval or acceptance to the seller, but retains the goods without giving notice of rejection, then if a time has been fixed for the return of the goods, on the expiration of such time, and, if no time has been fixed, on the expiration of a reasonable time. What is a reasonable time is a question of fact. (n)