Mechanical Spread Width
What it does
Dollar width of each defined-risk wing in dollars (or index points). The long wing is placed this far OTM from the short strike. User-selectable per account in $5 increments (5, 10, 15, or 20). A 10-wide iron condor with 20-delta shorts collects roughly $2.50 to $3.50 in premium and has a maximum loss of roughly $6.50 to $7.50 per contract.
When to change it
Narrow to 5 to reduce max loss per contract; premium collected drops proportionally. Widen to 15 or 20 to collect more premium and widen breakevens, at a larger max loss per contract.
Safe range
5 (tight, less premium, less risk) to 20 (wide, more premium, more risk).
Example
SPY iron condor, 10-wide wings: short put at $475, long put at $465, short call at $525, long call at $535. With a $3.00 credit collected, max loss per contract is $700 if SPY closes outside the wings at expiration.