The premium which you buy it for and the issued strike price. (The loan) With a roller the strike can change once a year (reduced) and you have to pay immediately the reduction plus interest to the issuer.
So say you have a roller covering stock A out 10 years.
Stock A is 10$ atm. Roller is trading at 5.50 with a 5.00 strike. You pay 5.50 for the roller and have the strike of 5.00 to pay. After 1 year the issuer can reduce the strike to say 4.00. You are then liable to pay immediately 1.00 plus interest or they will sell the equivalent number of rollers to make up this amount.
As time goes by the strike is progressively reduced and payments have to be made. A normal instalment is when the 'strike' or loan is fixed over the term of the warrant.
